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A proposed information system for concrete construction : a project and activity planning specification Turnham, James Richard 1988

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A PROPOSED INFORMATION SYSTEM FOR CONCRETE CONSTRUCTION: A PROJECT AND ACTIVITY PLANNING SPECIFICATION By James R. Turnham P. Eng. B.C.E. U n i v e r s i t y o f Minnesota, 1972 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF APPLIED SCIENCE i n The F a c u l t y o f Graduate S t u d i e s Department of C i v i l E n g i n e e r i n g We accept t h i s t h e s i s as conforming t o the r e q u i r e d standard. Dr. A. D. R u s s e l l Dr. W. F. C a s e l t o n U n i v e r s i t y o f B r i t i s h Columbia October, 1988 (S) James R i c h a r d Turnham, 1988 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of C I V I L E N G I N E E R I N G The University of British Columbia Vancouver, Canada Date October 3, 19 88 DE-6 (2/88) ABSTRACT Current useage of construction information systems i s lar g e l y confined to C r i t i c a l Path Method scheduling, accounting systems, and cost control database systems. The function of a c t i v i t y planning i s not d i r e c t l y addressed by any of these systems while information from a l l three systems i s required for a c t i v i t y planning. A c t i v i t y planning i s the i t e r a t i v e process of s e l e c t i n g construction elements from the project work breakdown structure, addressing the available d e t a i l s from the plans and s p e c i f i c a t i o n s , assembling e x i s t i n g experiential information on methods, p r o d u c t i v i t i e s , and production rates, brainstorming for new and or appropriate e x i s t i n g methods, and deciding on a course of action for each item i n the breakdown structure. The focus i s on a construction a c t i v i t y planning framework to be u t i l i z e d by superintendent l e v e l personnel. This thesis examines the l i t e r a t u r e and ex i s t i n g software to i d e n t i f y the technologies that are relevant to detailed a c t i v i t y planning. The concept of u t i l i z i n g "Planning Models" to address a c t i v i t y planning for repetitious concrete construction i s introduced. The "General A c t i v i t y Planning Model" provides the functions and instructions required for detailed project and a c t i v i t y planning of a generic concrete construction project. " S p e c i f i c Planning Models" ensue from the general model and two examples are provided to i l l u s t r a t e the process. The f i r s t example i s of a p o s t - t e n s i o n e d c o n c r e t e b r i d g e p r o j e c t . T h e s e c o n d i s o f a c u t a n d c o v e r s u b w a y t u n n e l p r o j e c t . F r o m t h e t w o e x a m p l e s , t h e k e y p l a n n i n g s y s t e m a t t r i b u t e s o f f u n c t i o n a n d f l e x i b i l i t y a r e d e m o n s t r a t e d . T h e f u n c t i o n s r e q u i r e d i n c l u d e : 1. P r o j e c t l e v e l w o r k b r e a k d o w n s t r u c t u r e a n d i n i t i a l i z a t i o n . 2 . A t w o p a s s s y s t e m f o r e s t i m a t i n g a n d p l a n n i n g . 3 . E a r l y c a l c u l a t i o n o f t a r g e t a c t i v i t y d u r a t i o n s f r o m m i l e s t o n e c o n s t r a i n t s . 4 . A c t i v i t y l e v e l , c o n t i n u o u s c r e w s c h e d u l i n g , w h e r e a p p r o p r i a t e , p r i o r t o d e t a i l d e s i g n o f m e t h o d s . 5 . O p e r a t i o n l e v e l i n p u t : m a j o r r e s o u r c e ( f o r m w o r k q u a n t i t y ) r e q u i r e m e n t s , d e c i s i o n v a r i a b l e s , c r e w s i z e v a r i a t i o n t o i m p l e m e n t d u r a t i o n c o n t r o l , a n d e q u i p m e n t l e v e l l i n g . T h e f l e x i b i l i t y o f t h e G e n e r a l P l a n n i n g M o d e l i s i l l u s t r a t e d b y t h e s u c c e s s f u l p l a n n i n g o f t w o d i s s i m i l a r p r o t o t y p e p r o j e c t s f r o m o n e g e n e r a l m o d e l . S p e c i f i c i s s u e s p e r t a i n i n g t o e a c h p r o j e c t a r e s t r u c t u r e d a n d s o l v e d b y e x a m p l e . C o m p u t e r s y s t e m i s s u e s a r e d i s c u s s e d . A d a t a b a s e s y s t e m i s i d e n t i f i e d a s t h e s o f t w a r e o f c h o i c e f o r t h e c o n s t r u c t i o n p l a n n i n g p r o b l e m . S e v e r a l c o m m e r c i a l l y a v a i l a b l e p r o g r a m s a r e e v a l u a t e d . I n t e g r a t i o n o f a c t i v i t y p l a n n i n g w i t h o t h e r c o n s t r u c t i o n s p e c i a l i t i e s i s i d e n t i f i e d i n f l o w c h a r t f o r m . - i v -TABLE OF CONTENTS CHAPTER 1 INTRODUCTION 1 1.1 Scope of Research 2 1.2 Statement of the Problem 3 1.3 The Expanded Problem Statement 7 CHAPTER 2 LITERATURE AND SOFTWARE SEARCH 9 2.0 Introduction 9 2.1 Software Search 9 2.1.1 Spreadsheet Technology 9 2.1.2 Multidimensional Spreadsheets 10 2.1.3 Project Management Software 12 2.1 .4 Database Software 15 2.2 Literature Review 16 2.2.1 Estimating 17 2.2.2 Planning and Scheduling 21 2.2.3 Productivity Forecasting and Enhancement Systems 25 2.2 .4 Decision Support and Expert Systems 3 0 2.2.4.1 Decision Support Systems 3 0 2.2.4.2 Expert Systems 3 3 2.2.5 Integrated Construction Systems 37 2.3 Not Found i n the Literature 41 CHAPTER 3 CONSTRUCTION INFORMATION SYSTEM FORMULATION.... 43 3.0 Introduction 4 3 3.1 Work Breakdown Structure 43 - v -3.2 Methodology 47 3.3 Fun c t i o n s Required For The Proposed System 50 3.4 Computer Environment Requirements For The Proposed System 51 3.5 A Proposed System In Two P a r t s : The 80 % S o l u t i o n 55 3.6 Pla n n i n g Models 56 3.6.1 B e n e f i t s of Using P l a n n i n g Models 58 3.6.2 G r a p h i c a l Techniques 59 3.6.3 The Models Presented.. 59 CHAPTER 4 GENERAL PLANNING MODEL FOR CONCRETE CONSTRUCTION 61 4.0 I n t r o d u c t i o n 61 4.0.1 General P l a n n i n g Model Flow Chart 62 4.0.2 Example Overview: Cambie Bridge Vancouver, BC 62 4.1 P r o j e c t L e v e l : Commencement of the Plan 66 4.1.0 The Estimate 66 4.1.1 P r o j e c t Award 66 4.1.2 P r o j e c t Work Breakdown S t r u c t u r e (WBS) .. 67 4.1.3 P r o j e c t C o n s t r a i n t s 69 4.1.4 Qua n t i t y Takeoff and Rate T a b l e s 70 4.1.5 Model The P r o j e c t 70 4.1.6 Co n t r a c t D u r a t i o n S p e c i f i e d ? 74 4.1.7 P r o j e c t Target Duration v s . Contract. D u r a t i o n 74 4.2 A c t i v i t y L e v e l Planning 76 4.2.1 Create and Define the A c t i v i t y 7 6 4.2.2 Model the A c t i v i t y 78 - v i -4.2.3 Crew Operation Schedule To Be Linear and Continuous? 82 4.2.4 Input Linear Constraints.... 84 4.2.5 Sort Operations 92 4.3 Operation Level 93 4.3.0 Introduction to Operation Level Design Parameters 93 4.3.0.1 Decision Variables 93 4.3.0.2 Required Output From Operation Planning 100 4.3.1 Create Operation Worksheet 102 4.3.2 Calculate Major Resource Requirements.... 105 4.3.3 Design Parameters 108 4.3.4 Cost Calculations 109 4.3.4.1 Material Cost Calculations 109 4.3.4.2 Labour Cost Calculations 110 4.3.4.3 Equipment Cost Calculations 110 4.3.4.4 Total Cost Per Option I l l 4.3.5 Last Option? Choose Minimum Cost Option 112 4.3.6 Calculate Crew Size and Test Duration.... 112 4.3.6.1 Crew Cycle Duration Specified, (Linear Planning) 113 4.3.6.2 Crew Cycle Duration Not Specified 114 4.3.7 Last Operation 114 4.4 A c t i v i t y Level Results 115 4.4.1 Major Equipment Resource L e v e l l i n g 115 4.4.2 Refinement of A c t i v i t y Schedule 118 4.4.3 Preliminary Design of A c t i v i t y i i s Complete 118 - v i i -4.4.4 Last A c t i v i t y ? 119 4.5 Project Results 119 CHAPTER 5. SYSTEM DESIGN ISSUES 120 5.0 Introduction 12 0 5.1 Conceptual Datafile Design 12 0 5.2 Da t a f i l e Design: Dbase Format and 5 Identity F i e l d s 122 5.2.1 D e f i n i t i o n f i l e s 123 5.2.2 Timesheet F i l e 124 5.2.3 Activity-Operation Data C o l l e c t i o n F i l e 126 5.2.4 A c t i v i t y Data C o l l e c t i o n Summary F i l e . . . . 128 5.2.5 Project Data C o l l e c t i o n F i l e Summary 12 8 5.2.6 Archived Data C o l l e c t i o n F i l e 128 5.2.7 New Estimating and Tendering F i l e s 129 5.2.8 Data Transformation F i l e 130 5.2.9 Planning and Scheduling F i l e s 131 5.3 Data f i l e Design Using a Multidimensional Spreadsheet 131 5.4 Software Command (Menu) Structure 136 CHAPTER 6. TESTING THE MODEL, THE SEATTLE CUT AND COVER TUNNELING EXAMPLE... 137 6.0 Introduction 13 7 6.1 Project: Seattle Cut and Cover Tunnel 13 9 6.1.1 Project Award: Brief Description of the Project 139 6.1.2 Project Work Breakdown Structure (WBS)... 140 6.1.3 Project Constraints 141 - v i i i -6.1.5 Model The Project 142 6.1.7 Target Duration 145 6.1.8 Subproject Continuity? Linear Scheduling Required? 147 6.1.8.1 Cycle Recognition 149 6.1.8.2 Cycle Design E f f i c i e n c i e s 150 6.1.8.3 Crew Cycle 151 6.1.8.4 M u l t i - a c t i v i t y Crew Scheduling 151 6.1.8.5 Contingencies 153 6.2 A c t i v i t y Level Planning 153 6.2.1 Create and Define the A c t i v i t y 154 6.2.2 Model the A c t i v i t y 157 6.2.3 Continuous or Linear Crew Scheduling?.... 158 6.3 Operation Level Testing 160 6.3.1 Create Operation Worksheet 160 6.3.2 Calculate Major Resource Requirements.... 162 6.3.3 Operation Design Parameters 164 6.3.6 Calculate Crew Size 165 6.4 Testing the Model: Results 168 CHAPTER 7 CONCLUSIONS 169 7.1 Accomplishments 169 7.2 Recommendations for Future Research 172 - i x -LIST OF FIGURES PAGE 1. Communication data l i n k s between c o n s t r u c t i o n 6 sub-systems. 2. Work i n s t r u c t i o n p l a n . (Revay) 28 3. Schedule of i n t e r p h a s i n g . (Revay) 29 4. Database management system f l o w c h a r t . (G. Law) 31 5. Design improvement and enrichment f l o w c h a r t . (G. Law) 32 6. Work breakdown s t r u c t u r e h i e r a r c h y . 44 7. Spreadsheet of r e q u i r e d f u n c t i o n s . 48-49 8. Fun c t i o n s s o r t e d by database, spreadsheet, and schedule. 53 9. General p l a n n i n g algorhythm f l o w c h a r t . 63 10. T y p i c a l c o n c r e t e b r i d g e s e c t i o n view. 68 11. Example WBS f o r a concre t e b r i d g e p r o j e c t . 69 12. P r o j e c t network example. 71 13. Target d u r a t i o n b a r c h a r t example. 72 14. Example WBS For Beam c o n s t r u c t i o n c y c l e . 77 15. Example d e c i s i o n t r e e f o r a c t i v i t y d e s i g n . 79 16. Example a c t i v i t y precedence network. 80 17. B a r c h a r t f o r a u n i t a c t i v i t y o f beam c o n s t r u c t i o n . 81 18. Example time space diagram. 82 19. Time-space diagram d e r i v i n g the standard crew c y c l e . 8 6 2 0a B a r c h a r t showing no o v e r l a p p i n g of o p e r a t i o n s . 89 Falsework requirement c a l c u l a t i o n example. 20b B a r c h a r t showing o v e r l a p p i n g of o p e r a t i o n s . 90 Falsework requirement c a l c u l a t i o n example. - x -21. Sub-operations versus d e c i s i o n v a r i a b l e s f o r o p e r a t i o n 96 formwork. 22. Time-space diagram showing falsework requirements. 106 23. Example crane resource schedule f o r "beam c o n s t r u c t i o n " . 117 24. D a t a f i l e overview f o r an i n t e g r a t e d c o n s t r u c t i o n 121 i n f o r m a t i o n system. 25. Example s t r u c t u r e f o r a p r o j e c t d e f i n i t i o n f i l e . 125 26. Example s t r u c t u r e f o r a d a i l y timesheet f i l e . 125 27. Example s t r u c t u r e f o r an a c t i v i t y and o p e r a t i o n data 127 f i l e . 28. Example s t r u c t u r e f o r a data t r a n s f o r m a t i o n f i l e s . 127 29. M u l t i - d i m e n s i o n a l spreadsheet s c r e e n showing dimensions 132 and headings. 30. M u l t i d i m e n s i o n a l spreadsheet s c r e e n showing phase ve r s u s 133 d e s c r i p t o r f i r o p e r a t i o n = shore f o o t i n g s . 31. M u l t i d i m e n s i o n a l spreadsheet: phase ve r s u s d e s c r i p t o r 13 4 f o r o p e r a t i o n = c o n c r e t e . 32. M u l t i d i m e n s i o n a l spreadsheet: phase versus l o c a t i o n . 135 33. Time-space diagram: exc a v a t i o n , l a g g i n g , and b r a c i n g 142 a c t i v i t i e s f o r s u b - p r o j e c t t u n n e l . 34. Time-space diagram f o r base s l a b , C l e v e l s t r u t , w a l l s , 143 and r o o f a c t i v i t i e s f o r s u b - p r o j e c t t u n n e l . 35. Sequence drawing: S e a t t l e cut and cover t u n n e l p r o j e c t . 144 36. Tunnel s u b p r o j e c t b a r c h a r t showing t a r g e t d u r a t i o n s . 14 5 37. P r o j e c t l e v e l r e v i s i o n t o the General P l a n n i n g Model. 148 38. Time-space diagram: M u l t i - a c t i v i t y l i n e a r crew 152 s c h e d u l i n g . 39. P r e l i m i n a r y b a r c h a r t f o r r o o f a c t i v i t y . 158 - x i -40. M u l t i - a c t i v i t y crew s c h e d u l i n g f o r w a l l and r o o f 159 a c t i v i t i e s . 41. Spreadsheet of o p t i o n s versus d e s c r i p t o r s f o r o p e r a t i o n 161 "shore and form r o o f " . 42. B a r c h a r t showing e f f e c t s of c o n s t r u c t i n g two segments 163 of r o o f a c t i v i t y a t one time. 43. B a r c h a r t showing m u l t i a c t i v i t y continuous crew 167 s c h e d u l i n g . - x i i -ACKNOWLEDGEMENTS "Thank God I'm done a t l a s t . " I wish t o take t h i s o p p o r t u n i t y t o recog n i z e those who have c o n t r i b u t e d t h e i r support d u r i n g the w r i t i n g of t h i s t h e s i s : my w i f e Lucy f o r her moral support; Dennis Semeniuk and SCI C o n t r a c t o r s Inc. f o r the op p o r t u n i t y t o p r a c t i c e some of the concepts contained i n t h i s t h e s i s on a l a r g e and demanding c o n s t r u c t i o n p r o j e c t ; and Dr. Alan R u s s e l l of the U n i v e r s i t y of B r i t i s h Columbia f o r h i s unwavering focus on the a c t i v i t y p l a n n i n g problem as the scope o f the t h e s i s ; t o each of these I express my g r a t i t u d e . James R. Turnham - 1 -CHAPTER 1 INTRODUCTION A c t i v i t y p l a n n i n g i s the process of determining how, when, and wit h what re s o u r c e s a work breakdown s t r u c t u r e component w i l l be c o n s t r u c t e d . "In i t s s i m p l e s t form, a c t i v i t y p l a n n i n g i n v o l v e s the d e t e r m i n a t i o n of an a c t i v i t y ' s d u r a t i o n as a f u n c t i o n of crew s i z e s , equipment i n p u t s , and p r o d u c t i v i t y r a t e s . In i t s most complex form, i t may i n v o l v e the use of s i m u l a t i o n ( 5 ) or work process models s i m i l a r t o precedence networks."(16) T y p i c a l l y , a c t i v i t y p l a n n i n g i n v o l v e s the f o l l o w i n g s t e p s : 1. i n p u t of c o n t r a c t u a l p l a n s and s p e c i f i c a t i o n s ; 2. c o n s i d e r a t i o n of the s i t e c o n d i t i o n s and c o n s t r a i n t s ; 3. i d e n t i f y d e c i s i o n v a r i a b l e s ; 4. development, d e t a i l i n g , and d r a f t i n g of a p l a n f o r the work; 5. a l l o c a t i o n o f r e s o u r c e s : manpower, equipment, m a t e r i a l s , and s u b - c o n t r a c t o r s ; 6. communication of the p l a n and schedule t o s i t e s u p e r v i s o r s f o r c o n s t r u c t i o n ; and 7. follow-up with a mo n i t o r i n g program. The o b j e c t i v e of t h i s r e s e a r c h i s to d e v i s e a c o n s t r u c t i o n i n f o r m a t i o n system t h a t addresses the day t o day problems and requirements of a c t i v i t y p l a n n i n g . - 2 -1 . 1 Scope o f the Research Co n c e p t u a l l y , t h i s r e s e a r c h has been c o n f i n e d t o the g e n e r a l area of r e p e t i t i o u s , c o n c r e t e c o n s t r u c t i o n . The c h o i c e o f co n c r e t e c o n s t r u c t i o n ' s p r i n g s from the o b s e r v a t i o n t h a t c o n c r e t e work u s u a l l y i n v o l v e s m u l t i p l e o p e r a t i o n s and crews and t h e r e f o r e r e q u i r e s an a d d i t i o n a l l e v e l of complexity t o be modelled i n the work breakdown s t r u c t u r e . The p o i n t here i s t h a t i f a breakdown s t r u c t u r e can model concre t e c o n s t r u c t i o n , i t w i l l be a p p l i c a b l e t o a broad range of c i v i l e n g i n e e r i n g p r o j e c t s . An e f f o r t has been made t o g e n e r a l i z e and v a l i d a t e the concepts developed by a p p l y i n g them t o ongoing, r e a l l i f e , p r o j e c t s . The f o l l o w i n g p r o j e c t s were examined: 1. The Cambie Bridge P r o j e c t ; a multispan, p o s t -t e n s i o n e d , c o n c r e t e b r i d g e c o n s t r u c t e d from 1983 to 1986 i n Vancouver, BC. 2. The Downtown S e a t t l e Tunnel P r o j e c t ; A c u t and cover subway t u n n e l p r o j e c t begun i n 1987 and p r e s e n t l y under c o n s t r u c t i o n i n S e a t t l e , Washington. These two p r o j e c t s p r o v i d e d the c o n s t r u c t i o n a c t i v i t i e s , c o n s t r a i n t s , problems, and exposure t o some of the s o l u t i o n s t h a t , as a whole, form the background f o r t h i s t h e s i s . - 3 -R e p e t i t i o n adds a s i g n i f i c a n t dimension t o the scope of p l a n n i n g , s c h e d u l i n g , and c o n t r o l requirements on a c o n s t r u c t i o n p r o j e c t . R e p e t i t i o n has the e f f e c t of adding a breakdown of the a c t i v i t y i n t o u n i t s c a l l e d " u n i t - a c t i v i t i e s " h e r e i n . While not e x t e n s i v e l y encountered i n the search of the l i t e r a t u r e , u t i l i z a t i o n of r e p e t i t i o u s c o n s t r u c t i o n p l a n n i n g t e c h n i q u e s w i t h i n c o n s t r u c t i o n i n f o r m a t i o n systems i s one of the c e n t r a l i s s u e s of t h i s t h e s i s . The r e p e t i t i o n f a c t o r a l s o f o r c e s one t o imagine, p l a n and f i n a l l y implement e f f i c i e n t methods t o accomplish the work. T h i s t e n e t f o l l o w s from economies of s c a l e p r i n c i p l e s . With l a r g e s c a l e r e p e t i t i o n , one can a f f o r d t o spend time and money up f r o n t i n the a c t i v i t y d e s i g n phase t o minimize u n i t expenses i n the c o n s t r u c t i o n phase. The more r e p e t i t i o u s the work, the more d e t a i l t h a t can be j u s t i f i e d i n the p l a n n i n g p r o c e s s . With the need f o r p l a n n i n g comes the need f o r systems t o p r o v i d e a s t r u c t u r e d p l a n n i n g environment and a t the same time the f l e x i b i l i t y t o accomodate change. 1.2 Statement o f the Problem What i s r e q u i r e d t o accomplish the design and p l a n n i n g of a c o n s t r u c t i o n a c t i v i t y ? How can the a c t i v i t y p l a n n i n g process be s t be s t r u c t u r e d ? How can a computer be u t i l i z e d t o p r o v i d e a framework and d e c i s i o n support system f o r the a c t i v i t y p l a n n i n g process? - 4 -T h i s t h e s i s began wi t h the above t h r e e q u e s t i o n s . While examining these q u e s t i o n s , the f o l l o w i n g i s s u e s became apparent: i ) S t a n d a r d i z a t i o n Use of a computer i n a c t i v i t y p l a n n i n g would r e q u i r e some s t a n d a r d i z a t i o n of the p l a n n i n g p r o c e s s . The g o a l i s t o i d e n t i f y an e f f i c i e n t methodology f o r p l a n n i n g and a software framework from which t o address a l l the nuances of a l l c o n c e i v a b l e a c t i v i t y p l a n s . One i s s u e t o address e a r l y on i s t h a t of p r o v i d i n g s u f f i c i e n t f l e x i b i l i t y i n the p l a n n i n g system t o a l l o w c o n s t r u c t i o n p l a n n e r s t o be c r e a t i v e and i m a g i n a t i v e w h i l e s t i l l working w i t h i n computerized c o n f i n e s . i i ) Source o f Data and Records A n a l y s i s of the p l a n n i n g process w i l l i n d i c a t e t h a t the p l a n n i n g process cannot operate i n a vaccuum. I t i s but one of many aspects of a c o n s t r u c t i o n p r o j e c t . F i r s t l y , a c t i v i t y p l a n n i n g r e q u i r e s t i m e - c o s t data with which t o e v a l u a t e each a l t e r n a t i v e c o n s i d e r e d f o r a l l aspects of the c o n s t r u c t i o n p r o j e c t . What are the sources of t h i s t i m e - c o s t i n f o r m a t i o n ? The f o l l o w i n g sources are h i g h l i g h t e d : 1 . P r o j e c t C o n t r o l H i s t o r i c a l l y , t i m e - c o s t records have come from paper f i l e s on jobs t h a t a company has p r e v i o u s l y c o n s t r u c t e d . T h e r e f o r e a l i n k i s r e q u i r e d from the h i s t o r i c a l t i m e - c o s t r e c o r d s developed i n the p r o j e c t c o n t r o l phase, to the a c t i v i t y p l a n n i n g f u n c t i o n . The r e l e v a n c e of such data t o the p r o j e c t a t hand must be c a r e f u l l y assessed. - 5 -2. Estimating and Planning Another obvious l i n k exists between estimating and planning. The estimator must price the a c t i v i t i e s for which the construction superintendent must l a t e r develop detailed plans. A planning system that u t i l i z e s the framework supplied f i r s t by the estimator reaps the benefits of the estimator's i n i t i a l data input and h i s broad brush conceptions of how the job might be b u i l t . 3. Planning and Scheduling A data l i n k also exists between planning and scheduling. The schedule w i l l often dictate the plan and vice versa and because of that fact, the two functions are often grouped into one. 4. Integration Planning i s one of many in t e r r e l a t e d aspects of the construction process and, as such, a c t i v i t y planning i s most e f f i c i e n t l y treated as part of an integrated system. The relationships between the various construction functions are i l l u s t r a t e d i n figure 1. I t also shows the communication l i n k s required by a construction information system. - 6 -Communication data l i n k s between c o n s t r u c t i o n sub-systems(1). F i g u r e 1. S i n c e one o f the g o a l s of t h i s t h e s i s i s t o develop a p r a c t i c a l , coherent statement f o r use i n developing a u s e f u l c o n s t r u c t i o n p l a n n i n g system, the d e c i s i o n was made to expand the scope of the t o p i c t o i n c l u d e the i n t e r f a c e of a c t i v i t y p l a n n i n g with the r e l a t e d f u n c t i o n s o f s c h e d u l i n g , e s t i m a t i n g , and p r o j e c t c o n t r o l . Thus the problem statement needs to be expanded. - 7 -1.3 The Expanded Problem Statement Design a s p e c i f i c a t i o n for a construction information system. S p e c i f i c tasks to be treated include the following: 1. Provide a conceptual overview of the estimating function considering the overlapping relationship with the a c t i v i t y planning function. 2 . Provide project inputs to the planning process. Provide the means to guide the planning process through the many phases of construction: from estimating to project award to target project durations to a c t i v i t y cycle design to detailed a c t i v i t y plans to project control to estimating. 3. Identify and describe the a c t i v i t y planning function and specify an information system that addresses the key inputs, design processes, and required outputs. 4 . Provide the conceptual interface from project control records to the a c t i v i t y planning function. 5 . Provide the applicable interface for p a y r o l l , accounts payable, and accounts receivable . - 8 -6. I l l u s t r a t e the planning / scheduling interface c a p a b i l i t y . 7 . Develop a detailed l i s t of functions including descriptions and examples for a l l system c a p a b i l i t i e s . 8 . Determine which environment or software would be best suited for system development. - 9 -CHAPTER 2 LITERATURE AND SOFTWARE SEARCH 2.0 I n t r o d u c t i o n In t h i s chapter, e x i s t i n g software and the l i t e r a t u r e p e r t a i n i n g t o t he s u b j e c t of c o n s t r u c t i o n p l a n n i n g are examined. The software search y i e l d e d i n f o r m a t i o n on computer environments a p p l i c a b l e f o r a c t i v i t y p l a n n i n g . The l i t e r a t u r e s e a r c h examines both computer environments and f u n c t i o n s t h a t are a p p l i c a b l e f o r c o n s t r u c t i o n a c t i v i t y p l a n n i n g . 2.1 Software Search 2.1.1 Spreadsheet Technology Lotus 12 3, being easy t o use and one of the most p o p u l a r spreadsheet programs, was the begin n i n g p l a c e f o r t h i s r e s e a r c h p r o j e c t . Other r e s e a r c h i n c l u d i n g J . L. Rounds(15), i n d i c a t e d t h a t spreadsheets were a u s e f u l and e f f i c i e n t t o o l i n the p r e p a r a t i o n o f c o n s t r u c t i o n estimates f o r tender. Could Lotus a l s o be u s e f u l f o r p r o j e c t c o n t r o l and scheduling? The s h o r t answer v i s - a - v i s p r o j e c t c o n t r o l i s t h a t Lotus 12 3 can handle the data r e c o r d i n g f u n c t i o n but not e f f i c i e n t l y . U sing Lotus would r e q u i r e t h a t timesheet i n f o r m a t i o n would have t o be i n p u t c e l l by c e l l w i t h much s c r o l l i n g through the sheet t o l o c a t e the proper area f o r data e n t r y . The same s c r o l l i n g would be necessary when - 10 -one wanted t o f i n d the p e r t i n e n t data f o r a p a r t i c u l a r o p e r a t i o n or a c t i v i t y . The c o n c l u s i o n a r r i v e d a t i s t h a t spreadsheets are not e f f i c i e n t f o r t h i s k i n d of data s t o r a g e . When attempting t o use Lotus as a s c h e d u l i n g t o o l , the t a s k of p r e s e n t i n g i n f o r m a t i o n g r a p h i c a l l y i n b a r c h a r t form was found t o be d i f f i c u l t and awkward. Lotus 123 does an e x c e l l e n t job at c o m p i l i n g m a t e r i a l q u a n t i t i e s from c o n t r a c t drawings. The matrix format f o r c o m p i l i n g dimensions versus items and summing t o t a l s works w e l l . Another p o s s i b l e avenue worth e x p l o r i n g i s s i d e by s i d e comparison of i d e n t i f i e d c o n s t r u c t i o n methods. The a n a l y s i s of c o n s t r u c t i o n t e c h n o l o g i e s w i t h r e s p e c t t o c o s t s , d u r a t i o n s , and r e s o u r c e requirements would l i k e l y prove spreadsheets t o be u s e f u l and e f f i c i e n t a t t h i s t a s k . T h i s aspect of c o n s t r u c t i o n i n f o r m a t i o n a n a l y s i s w i l l be covered i n d e t a i l i n Chapter 4.3. 2.1.2 M u l t i d i m e n s i o n a l Spreadsheets A r e l a t i v e l y new breed of spreadsheet, the 3 dimensional and m u l t i d i m e n s i o n a l spreadsheet such as L u c i d , Boeing C a l c , and TM1 are environments of i n t e r e s t . - 11 -B o e i n g C a l c i s o r g a n i z e d b y t h e f a m i l i a r r o w / c o l u m n f o r m a t w i t h t h e a d d i t i o n o f t h e " p a g e " d i m e n s i o n w h i c h m a k e s i t t h r e e d i m e n s i o n a l . I t w a s t h e f i r s t o f t h e s e t h r e e p r o d u c t s o n t h e m a r k e t a n d h a s a h i g h l y r e s p e c t e d g r a p h i c s p a c k a g e t h a t a c c o m p a n i e s i t . L u c i d i s a t h r e e d i m e n s i o n a l s p r e a d s h e e t w i t h a n u m b e r o f i n t e r e s t i n g f e a t u r e s : 1. M e m o r y r e s i d e n t . I t r e s i d e s i n c o m p u t e r m e m o r y a t a l l t i m e s , e v e n d u r i n g e x e c u t i o n o f a n o t h e r p r o g r a m . I t c a n b e a c t i v a t e d t o t h e f o r e g r o u n d a n d r e t u r n e d t o t h e b a c k g r o u n d w i t h o n e k e y s t r o k e . 2 . A n y c e l l c a n c o n t a i n a c o m p l e t e s p r e a d s h e e t o f t h e n e x t l o w e r l e v e l . F o r i n s t a n c e , t h e u p p e r s h e e t w o u l d c o n t a i n a c e l l c o n t a i n i n g t h e f o r m u l a t h a t t o t a l l e d t h e c o s t s o f t h e l o w e r s h e e t . T h e n a n y c h a n g e t o t h e v a l u e s i n t h e l o w e r s h e e t w i l l b e r e f l e c t e d i n t h e v a l u e o f t h e t o t a l w h i c h i s d i s p l a y e d o n t h e u p p e r s h e e t . T h i s i s c a l l e d n e s t e d s p r e a d s h e e t s . 3 . N o t e p a d c o n t a i n e d b e h i n d e v e r y c e l l . ( T h i s c o n c e p t w o u l d b e a n e f f i c i e n t m e t h o d o f s t o r i n g m e t h o d s o r d e s c r i p t i o n s p e r t a i n i n g t o a c t i v i t i e s o r r e s o u r c e s i n a c o n s t r u c t i o n i n f o r m a t i o n s y s t e m . ) - 12 -TM1 i s a true multidimensional database that c a l l s i t s e l f a table manager. Data i s stored i n the table with dimensions making up the axes for row, column, page, etc. Each dimension i s a l i s t of common items that would be used to form the column or row headers. Tables are used to store data with up to 8 dimensions of data i d e n t i t y . With t h i s software, a piece of information could be categorized, for instance, by 1. Project, 2. Division, 3. A c t i v i t y , 4. Operation, 5. Location, 6. Resource, 7. Time or Cost, 8. Phase, (Bid estimate, Current estimate, or Actual). With such an organization c a p a b i l i t y , one could query the system for the following: a l l Projects, A c t i v i t y = beams, Operation = rebar, a l l Locations, Resource = laborer, Costs, Phase = actuals. For t h i s example, one would receive a l i s t of a l l the actual. labor, cost records for placing rebar i n beams for a l l projects in the company records at a l l locations s p e c i f i e d . The power and f l e x i b i l i t y of such a database would appear to be useful for the multidimensional nature of construction projects. 2 . 1 . 3 Project Management Software There are many useful project management / scheduling software packages commercially available. Timeline and Primavera Project Planner have been singled out here as examples representing two - 13 -ends of the p r o j e c t management software spectrum. T i m e l i n e i s w e l l r e s p e c t e d f o r i t s user f r i e n d l i n e s s , thorough documentation, o n - l i n e t u t o r i a l , f u n c t i o n a l i t y and inexpensive p r i c e . With very l i t t l e t r a i n i n g , a manager can model a c o n s t r u c t i o n p r o j e c t i n c o n s i d e r a b l e d e t a i l , s e t d u r a t i o n s , l a g s , precedence r e l a t i o n s , a s s i g n resources and c o s t s , and get both b a r c h a r t and precedence schedules as output. On the down s i d e , i t does not have coding c a p a b i l i t y which i s u s u a l l y c o n s i d e r e d e s s e n t i a l f o r most medium and l a r g e c o n s t r u c t i o n companies. Primavera, f o r i t s p a r t , has e s t a b l i s h e d a r e p u t a t i o n f o r being one of the most e x t e n s i v e , powerful, and v e r s a t i l e p r o j e c t management t o o l s on the market. I t s drawbacks i n c l u d e a much l a r g e r purchase p r i c e and a st e e p e r l e a r n i n g curve a s s o c i a t e d w i t h the g r e a t e r a r r a y o f f u n c t i o n s and c a p a b i l i t i e s . The f o l l o w i n g i s a b r i e f d e s c r i p t i o n o f the some of the a t t r i b u t e s o f P r o j e c t Management Software i n g e n e r a l . i ) Systems c a p a b i l i t i e s A c t i v i t y d e s c r i p t i o n D u r a t i o n i n p u t M i l e s t o n e o r precedence i n p u t Lead-lag input Resource input by t r a d e or item G o s t i n g by resource time u n i t Calendar f l e x i b i l i t y Reports by many d i f f e r e n t formats - 14 -F l o a t c a l c u l a t i o n Resource l e v e l l i n g P r o j e c t cash flow m o d e l l i n g i i ) General systems l i m i t a t i o n s : L i m i t e d database c a p a b i l i t y . Data s t o r e d by a r c h i v e d schedules. No r e t r i e v a l of data by f i e l d name as per a database system P r o j e c t management software occupies a c o r n e r s t o n e i n c o n s t r u c t i o n i n f o r m a t i o n systems. Most of these software systems are b u i l t around a network p r o c e s s o r and o r g a n i z e a c t i v i t i e s , a s s o c i a t e d c o s t s and resources a c c o r d i n g t o the r e s u l t i n g network schedule. However, most of these s c h e d u l i n g systems r e q u i r e t h a t you, the scheduler, b r i n g a l l of the necessary i n f o r m a t i o n t o the network. Only w i t h d u r a t i o n s , l a g s , and precedence i n p u t w i l l i t c a l c u l a t e a schedule. Access t o d e t a i l e d i n f o r m a t i o n concerning methods, c o s t s , d u r a t i o n s , and p r o d u c t i v i t i e s a t the a c t i v i t y l e v e l i s r e q u i r e d f o r e f f i c i e n t a c t i v i t y p l a n n i n g . The use of a r c h i v e d schedules t o h e l p r e c o n s t r u c t past p r o j e c t a c t i v i t i e s , methods, p r o d u c t i o n r a t e s , l a b o r r a t e s and use of overtime i s p o s s i b l e but t e d i o u s with most systems. No micro computer system has been found t h a t c o n t a i n s a b u i l t i n database to expedite the r e t r i e v a l of h i s t o r i c a l i n f o r m a t i o n . P r o j e c t management software has a d e f i n i t e p l a c e i n a c o n s t r u c t i o n i n f o r m a t i o n system. I t i s an - 15 -e s s e n t i a l t o o l f o r the o r g a n i z a t i o n of the b i g p i c t u r e i n v o l v i n g many l o g i c l i n k s . However, f o r the c o l l e c t i o n and r e t r i e v a l of experience based i n f o r m a t i o n , e x i s t i n g p r o j e c t management software i s not the answer. 2.1.4 Database Software Si n c e c o n s t r u c t i o n p r o j e c t s r e q u i r e the t r a c k i n g of time and money expenditures f o r a l a r g e number of a c t i v i t i e s , i t f o l l o w s t h a t database software c o u l d be an a p p r o p r i a t e t o o l f o r o r g a n i z i n g , s t o r i n g and r e t r i e v i n g p r o j e c t c o n s t r u c t i o n i n f o r m a t i o n . The g e n e r a l c a p a b i l i t i e s and l i m i t a t i o n s of database software a v a i l a b l e f o r today's microcomputers l i s t s as f o l l o w s . i ) C a p a b i l i t i e s 1. Data r e t r i e v a l by c r i t e r i a or combination of c r i t e r i a . 2. Programmable language f a c i l i t a t i n g user f r i e n d l y prompting and c u s t o m i z a t i o n . 3. Spreadsheet importing: estimate spreadsheet e a s i l y i n t e r f a c e d with p r o j e c t c o n t r o l database. 4. Automated t r a n s f e r of data between f i l e s . 5. E a s i l y t a i l o r e d data s t r u c t u r e t o accomodate the data requirements of v a r i o u s p r o j e c t s . - 1 6 -i i ) L i m i t a t i o n s : 1 . G r a p h i c s v e r y m a r g i n a l o n t h e p r o g r a m s r e s e a r c h e d h e r e i n a l t h o u g h s o m e n e w s o f t w a r e h a s r e c e n t l y a p p e a r e d o n t h e m a r k e t t o a d d r e s s t h i s i n a d e q u a c y . 2 . L o g i c b e t w e e n a c t i v i t i e s n o t e a s i l y r e p r e s e n t e d . 3 . N o t s o p h i s t i c a t e d a s s c h e d u l i n g t o o l s . D a t a b a s e s o f t w a r e w o u l d s e e m m a d e t o o r d e r f o r c o n s t r u c t i o n i n f o r m a t i o n s t o r a g e a n d r e t r i e v a l . L o ( 9 ) u s e d D b a s e I I t o c o n s t r u c t a n i n f o r m a t i o n s y s t e m f o r r e s i d e n t i a l h o u s i n g c o n s t r u c t i o n . T h e r e a r e m a n y d a t a b a s e p r o g r a m s a v a i l a b l e o n t h e m a r k e t . A m o n g t h e m d B a s e I I I + , R b a s e S y s t e m 5 a r e n o t e w o r t h y . 2 . 2 L i t e r a t u r e R e v i e w S p e c i a l i z e d o r c u s t o m i z e d s o f t w a r e i s p e r h a p s t h e m a i n e n v i r o n m e n t f o r i n v e s t i g a t i o n w h e n t h e g o a l i s a c o n s t r u c t i o n i n f o r m a t i o n s y s t e m . T h i s s o f t w a r e i s h a r d t o f i n d i n a d e m o n s t r a t i o n f o r m a t o r a t a p r i c e t h a t c o u l d b e t o l e r a t e d b y a l l b u t t h e r i c h e s t o f r e s e a r c h e r s , b u t t h e l i t e r a t u r e r e v i e w s a r e a v a i l a b l e t h a t d o c u m e n t s o f t w a r e d e v e l o p m e n t s i n m a n y a r e a s o f t h e c o n s t r u c t i o n i n d u s t r y . T h o s e w h i c h a r e o f i n t e r e s t t o t h i s t h e s i s p e r t a i n e d t o t h e f o l l o w i n g a r e a s o f c o n s t r u c t i o n : - 17 -1. E s t i m a t i n g . 2. Pla n n i n g and s c h e d u l i n g . 3. P r o d u c t i v i t y f o r e c a s t i n g and enhancement. 4. D e c i s i o n support and expert systems 5. P r o j e c t management and c o s t c o n t r o l . 6. I n t e g r a t e d c o n s t r u c t i o n systems. In each of the above areas, the f o l l o w i n g q u e s t i o n s were of i n t e r e s t t o t h i s r e s e a r c h : 1. What framework or environment i s proposed? 2. What f u n c t i o n s are proposed w i t h i n each system t o pr o v i d e o r u t i l i z e the i n f o r m a t i o n r e q u i r e d ? 3. How would the system i n q u e s t i o n i n t e r f a c e t o the a c t i v i t y p l a n n i n g f u n c t i o n ? The f o l l o w i n g r e p r e s e n t a summary of the f i n d i n g s from a review of the l i t e r a t u r e . 2.2.1 E s t i m a t i n g E s t i m a t i n g i s an element of a c o n s t r u c t i o n i n f o r m a t i o n system which i s q u i t e w e l l supported i n the l i t e r a t u r e and i n e x i s t i n g software systems. The f o l l o w i n g systems are o u t l i n e d t o s t i m u l a t e i n t e r e s t i n the e s t i m a t i n g / p l a n n i n g i n t e r f a c e . T h i s r e s e a r c h does not e l a b o r a t e on the s u b j e c t of e s t i m a t i n g except to o u t l i n e these b a s i c f i n d i n g s . - 18 -The s i m p l e s t system was mentioned i n Chapter 2.1 and uses spreadsheet technology to c o n s t r u c t q u a n t i t y survey, p r i c i n g , and recap templates.(15) A software system c a l l e d I n t e r a c t i v e E s t i m a t i n g f o r C i v i l  E n g i n e e r i n g ^ ) l i s t s the f o l l o w i n g types of e s t i m a t e s and f e a t u r e s r e q u i r e d by an e s t i m a t i n g system: a) O p e r a t i o n a l estimate: b u i l d up o p e r a t i o n a l r e s o u r c e groups and c a l c u l a t e t h e i r t o t a l c o s t on an elapsed-time b a s i s , then a p p o r t i o n t h i s c o s t t o b i l l of q u a n t i t y items. b) U n i t r a t e estimate: b u i l d u n i t r a t e e s t i m a t e s u s i n g r e s o u r c e s and the a p p r o p r i a t e output or usage r a t e s from f i r s t p r i n c i p l e s on the screen. c) U n i t r a t e estimate: use b u i l d - u p s s t o r e d on the computer f i l e s and r e c a l l them t o the s c r e e n . d) Spot r a t e estimate: supply l a b o r , p l a n t , and m a t e r i a l r a t e s without c a l c u l a t i o n . e) Sub-contract: supply s u b - c o n t r a c t q u o t a t i o n s . f) "Included i n " c a p a b i l i t y : i n c l u d e the b i l l item i n the estimate f o r another item. - 19 -g) Include nominated s u b - c o n t r a c t o r s ' and s u p p l i e r s ' r a t e s w i t h attendances and p r o f i t s . i ) P r o v i s i o n a l sums. Another e s t i m a t i n g system c a l l e d INES ( I n t e r a c t i v e E s t i m a t i n g  Systems) i s of i n t e r e s t because of i t s use of a d e c i s i o n support system t o a i d e the e s t i m a t o r i n i d e n t i f y i n g the exact nature of a c o s t item.(6) INES i s b u i l t on 3 f i l e s : 1. L i b r a r y of standard items. 2. Cost a n a l y s i s of standard items. 3. Cost database of standard items. The l i b r a r y o f standard items i n c l u d e s Item number, Item code, Item d e s c r i p t i o n , and Item u n i t of measure. The Cost a n a l y s i s of standard items f i l e c o n t a i n s f o r each item a p r o g r e s s i o n of ques t i o n s t o be used by INES. The f u n c t i o n of these q u e s t i o n s i s t o breakdown the estimate of the item i n t o an a n a l y s i s o f i t s component p a r t s . The c o s t database f i l e c o n t a i n s i n f o r m a t i o n r e q u i r e d by INES i n order t o perform the a n a l y s i s p r o g r e s s i o n s t o r e d f o r a p a r t i c u l a r item i n the c o s t a n a l y s i s f i l e . I nformation i n t h i s f i l e may i n c l u d e : - 20 -1. m a t e r i a l p r i c e s , 2. wages f o r d i f f e r e n t t r a d e s , 3. waste percentages, 4. p r o d u c t i v i t y r a t e s , 5. equipment c o s t s , 6. s u b c o n t r a c t o r p r i c e s , and 7. o t h e r i n f o r m a t i o n s e l e c t e d by the e s t i m a t o r . The i n f o r m a t i o n i n t h i s f i l e i s the data f o r the d e c i s i o n support system and the data f o r the answers t o q u e s t i o n s c o n t a i n e d i n the a n a l y s i s f i l e . The A n a l y s i s f i l e uses a q u e s t i o n and answer procedure t o l e a d the e s t i m a t o r through the estimate. The f o l l o w i n g i s an example: P r o j e c t t i t l e ? Date of Estimate? Item code? Ans. 033009. Item 033009 = r e i n f o r c i n g s t e e l , #4 bar. Q u a n t i t y / u n i t ? Ans. 10.01 tons. B a s i c p r i c e i n database = $410.00 / ton. L a s t update = 11/2/85. Do you want t o use t h i s p r i c e ? Y/N Ans. No What p r i c e w i l l you use? Ans. $415.00 / ton. Do you want to change the database to t h i s value? Y/N? Ans. No. E t c . - 21 -The system i s a form of d e c i s i o n support system w i t h b u i l t i n knowledge i n the form of q u e s t i o n s and p r e - i d e n t i f i e d answers. The system i s f l e x i b l e as i s evidenced by the a b i l i t y of the e s t i m a t o r t o change the data and the q u e s t i o n s i n the database. A shortcoming i s the a b i l i t y t o p r o v i d e o n l y a s i n g l e v a l u e f o r an answer i n s t e a d of a matrix of v a l u e s f o r d i f f e r e n t c ircumstances. 2.2.2 P l a n n i n g and S c h e d u l i n g Two a r t i c l e s of c o n f l i c t i n g p h i l o s o p h y are examined here. O p t i m i z a t i o n as a P l a n n i n g S t r a t e g y The f i r s t a r t i c l e , C o n s t r u c t i o n Planning and S c h e d u l i n g System f o r C i v i l E n g i n e e r i n g Works (18), p r e s e n t s a system f o r o p t i m i z a t i o n of c o n s t r u c t i o n resource a l l o c a t i o n , ( i e . manpower, m a t e r i a l s , and equipment) on earthwork and heavy c i v i l p r o j e c t s . The program u t i l i z e s the f o l l o w i n g work breakdown s t r u c t u r e : 1. work areas: breakdown of l o c a t i o n s ; 2. work c a t e g o r i e s : 400 d i v i s i o n s of work d i v i d e d i n t o a t h r e e t i e r h i e r a r c h y ; 3. l o c a l c o n d i t i o n s : c l i m a t i c , g e o g r a p h i c a l , and g e o l o g i c a l c o n d i t i o n s ; and 4. equipment kinds and c l a s s e s : ( s e l f e x p l a n a t o r y ) . - 2 2 -A d a t a b a s e c o n t a i n i n g m a t e r i a l s , w o r k e r s k i l l s , w o r k e r c a p a c i t i e s , e q u i p m e n t p r o d u c t i o n r a t e s , a n d u n i t p r i c e s i s u t i l i z e d t o p r o v i d e t h e i n p u t d a t a u p o n w h i c h t h e o p t i m i z a t i o n w i l l b e p e r f o r m e d . T h e p r o g r a m u t i l i z e s t h e t e c h n i q u e o f l i n e a r p r o g r a m m i n g t o o p t i m i z e t h e r e s o u r c e a l l o c a t i o n p r o b l e m . T h e f o l l o w i n g p r o c e d u r e i s g i v e n f o r t h e c o n s t r u c t i o n o f a s o l u t i o n s e t . 1. N e t w o r k a n a l y s i s . 2 . F o r m u l a t i o n o f n o n l i n e a r m a t h e m a t i c a l m o d e l s . 3 . C o n s t r u c t i o n o f a l i n e a r a p p r o x i m a t i o n f r o m t h e n o n l i n e a r m a t h e m a t i c a l m o d e l s b y r e d u c i n g t h e o r i g i n a l p r o b l e m t o a s e t o f l i n e a r p r o g r a m m i n g p r o b l e m s ( L P s ) . 4 . O p t i m a l s o l u t i o n s e a r c h b y a b r a n c h a n d b o u n d a l g o r i t h m . S i m p l e x m e t h o d , d u a l s i m p l e x m e t h o d a n d p o s t o p t i m a l t e c h n i q u e a r e u s e d t o s o l v e t h e s e L P s . F o r t h e t h r e e r e s o u r c e s , m a n p o w e r , e q u i p m e n t , a n d m a t e r i a l s , t h e o b j e c t i v e f u n c t i o n i s t h e t o t a l e x p e n d i t u r e o f t h e r e s o u r c e i n q u e s t i o n . O p t i m a l a l l o c a t i o n i s t h e a l l o c a t i o n w h i c h n e e d s m i n i m a l e x p e n d i t u r e o n t h e r e s o u r c e . S y s t e m o u t p u t s i n c l u d e : 1. a l l o c a t i o n g r a p h s f o r m a n p o w e r , e q u i p m e n t , m a t e r i a l , a n d w o r k . 2 . p r o g r e s s g r a p h s f o r c o n s t r u c t i o n a r e a s a n d w o r k a r e a s . 3 . w o r k s c h e d u l e s f o r e v e r y c o n s t r u c t i o n a r e a . 4 . c o m b i n a t i o n o f c o n s t r u c t i o n e q u i p m e n t f o r e v e r y w o r k s i n e v e r y m o n t h . - 2 3 -The authors of the above reviewed a r t i c l e c l a i m t h a t the above system i s b e i n g used s u c c e s s f u l l y on heavy c o n s t r u c t i o n p r o j e c t s . The concept of u s i n g l i n e a r programming f o r o p t i m i z i n g the a l l o c a t i o n of heavy equipment on l a r g e s c a l e e a r t h moving jobs sounds reasonable. Many kinds of machines are a v a i l a b l e . C a p a c i t i e s of the machines i n d i f f e r e n t s o i l c o n d i t i o n s are q u a n t i f i a b l e . The p a y o f f f o r an optimal or near o p t i m a l s o l u t i o n c e r t a i n l y e x i s t s . The q u e s t i o n a r i s e s , "How e x t e n s i v e l y and t o which elements of c o n c r e t e c o n s t r u c t i o n can l i n e a r programming be e f f i c i e n t l y a p p l i e d ? " I m p l i c a t i o n P l a n n i n g as a S t r a t e g y The second a r t i c l e , " C o n s t r u c t i o n P l a n n i n g and C o n t r o l , Current P r a c t i c e and C o n t i n u i n g C h a l l e n g e s " ( 1 7 ) , s e t s out t o debunk the n o t i o n t h a t o p t i m i z a t i o n can be e f f e c t i v e l y a p p l i e d o u t s i d e of c o n s t r u c t i o n academic i n s t i t u t i o n s . " O p t i m i z a t i o n i s not being achieved i n the i n d u s t r y and i t i s the w r i t e r ' s c o n t e n t i o n t h a t i t should not be sought." The p h i l o s o p h y put foreward i s " I m p l i c a t i o n p l a n n i n g " , a s t r a t e g y of c o n v e n t i o n a l p l a n n i n g to be r e f i n e d by computer c a p a b i l i t y . "The concept of i m p l i c a t i o n p l a n n i n g i s t o c o n t i n u a l l y assess the i m p l i c a t i o n s of i n t u i t i v e - b a s e d d e c i s i o n s r a t h e r than t o attempt t o c r e a t e the d e c i s i o n s through mathematical a n a l y s i s . " - 24 -"The s i n g l e most important f e a t u r e of t h i s p r o c e s s i s t h a t the f a s t e r and more e f f i c i e n t u t i l i z a t i o n o f human assessment i s combined more e f f e c t i v e l y w i t h the slower and more r i g i d mathematical p r o c e s s e s . " T h i s a r t i c l e p r o v i d e s the f o l l o w i n g l i s t o f procedures: 1 . . " S e l e c t a c t i v i t y format", s e l e c t l e v e l of d e t a i l . 2. "Compile l o g i c diagram", an i t e r a t i v e procedure. 3. " C a l c u l a t e d u r a t i o n s " , based on: q u a n t i t y of work res o u r c e a p p l i c a t i o n p r o d u c t i v i t y and output method statement environmental r e s t r a i n t s 4. "Resource a n a l y s i s - smoothing S t a p e l b e r g ' s main c o n c l u s i o n s are as f o l l o w s : 1. The complexity of p l a n n i n g a p r o j e c t i s g e n e r a l l y underestimated by the t h e o r i s t and the computer a n a l y s t . 2. The computer u s e r / p l a n n e r should be g i v e n the f a c i l i t y t o process p o l i c y d e c i s i o n s simply and e f f e c t i v e l y i n a mode which does not r e p l a c e l o g i c a l t h i n k i n g but m a g n i f i e s and a n a l y s e s the i m p l i c a t i o n s of such d e c i s i o n s . 3. Computer systems should f a c i l i t a t e a mixture of bar c h a r t , c r i t i c a l path, p e r t and l i n e of balance systems s i m u l t a n e o u s l y i n a j o i n t and s e v e r a l a s s o c i a t i o n . - 25 -4. Data p r e p a r a t i o n should be kept a t the most s i m p l i s t i c l e v e l p o s s i b l e . 5. R e p o r t i n g should be g r a p h i c a l where p o s s i b l e and should c o n t a i n comprehensive i m p l i c a t i o n a n a l y s e s . 6. I t i s v i t a l t o remember t h a t p l a n n i n g systems are e s s e n t i a l l y * d e c i s i o n support systems 7 and, t h e r e f o r e , the t i m e l y d e l i v e r y of the goods i s as important, i f not more important, than the accuracy of the r e s u l t s . The above a r t i c l e espousing i m p l i c a t i o n p l a n n i n g i s q u i t e c o n t r a r y t o the p r e v i o u s a r t i c l e on o p t i m i z a t i o n u s i n g l i n e a r programming. T h i s t h e s i s chooses a tack more i n l i n e with i m p l i c a t i o n p l a n n i n g than with o p t i m i z a t i o n . The premise f o r t h i s d i r e c t i o n i s "One step a t a time". Research may show t h a t the o p t i m i z a t i o n approach may one day be v i a b l e f o r c o n s t r u c t i o n management. For t h i s t h e s i s , the e f f o r t i s d i r e c t e d toward a system whereby management i n i t i a t e s the methods and the computer a s s i s t s w i t h a n a l y s i s of the r e s u l t i n g p l a n . 2.2.3 P r o d u c t i v i t y F o r e c a s t i n g and Enhancement Systems The l i t e r a t u r e gathered i n d i c a t e s t h a t t h i s t o p i c i s software independent. Systems i n v o l v e d i n p r o d u c t i v i t y f o r e c a s t i n g and enhancement may or may not u t i l i z e a computer. N e v e r t h e l e s s , - 26 -t h i s t o p i c i s important f o r c o n s t r u c t i o n and f o r c o n s t r u c t i o n a c t i v i t y p l a n n i n g i n f o r m a t i o n systems. Two a r t i c l e s are d i s c u s s e d r e g a r d i n g p r o d u c t i v i t y . Both are of i n t e r e s t t o t h i s r e s e a r c h t o the extent t h a t they i n v o l v e a c t i v i t y p l a n n i n g . The f i r s t , Labor P r o d u c t i v i t y and Manpower  F o r e c a s t i n g ( 3 ) , d i s c u s s e s the impact and c o s t o f overtime useage. C i t e d i n the a r t i c l e i s the h i g h c o s t o f the use of scheduled overtime. A 1980 study by a ta s k f o r c e of the Business Roundtable i n d i c a t e s t h a t 60 hour weeks worked over a prolonged p e r i o d may cause p r o d u c t i v i t y t o drop t o 65% of t h a t o b t a i n e d on normal 4 0 hour weeks. The drop i s i n f l u e n c e d by the i n c r e a s e i n wages and by the drop i n p r o d u c t i o n per hour. The a r t i c l e a l s o mentions 6 other p r o d u c t i v i t y f a c t o r s w i t h i n management c o n t r o l : worker d e n s i t y c r a f t t r a i n i n g work p l a n n i n g proper and s u f f i c i e n t t o o l s c o r r e c t m a t e r i a l s s u p e r v i s i o n q u a l i t y These are nuts and b o l t s i s s u e s f o r c o n s t r u c t i o n management t o the p o i n t where they may o f t e n be i n a d v e r t a n t l y taken f o r granted i n the quest f o r h i g h e r p r o f i l e and more powerful management systems. The p o i n t i s , these are the d e t a i l s t h a t l e a d t o e f f i c i e n t or i n e f f i c i e n t o p e r a t i o n s on the job s i t e . Management systems and i n f o r m a t i o n systems need t o address these i s s u e s . - 27 -The second a r t i c l e , Improved P r o d u c t i v i t y Through I n t e g r a t i n g  Work I n s t r u c t i o n s With Progress C o n t r o l ( 1 4 ) , p r i m a r i l y addresses the problem of t r a n s l a t i n g the p r o j e c t l e v e l p l a n n i n g systems t o meaningful work i n s t r u c t i o n p l a n s . The major p o i n t s of the t r a n s l a t i o n framework are as f o l l o w s : 1. The "work i n s t r u c t i o n p l a n " i s based on the commonly used " s h o r t c y c l e schedule" c o v e r i n g a t h r e e week i n t e r v a l . 2. The f r o n t page c o n t a i n s the i n f o r m a t i o n necessary f o r e f f i c i e n t time management, i . e . b a r c h a r t , q u a n t i t y estimates, and resource d i s t r i b u t i o n f o r e c a s t s (see f i g u r e s 2 and 3). 3. Manpower and equipment c a t e g o r i e s c o n t a i n space f o r both planned and a c t u a l resource a l l o c a t i o n . The foremen are r e q u i r e d t o r e c o r d the a c t u a l s on a d a i l y b a s i s . 4. Side 2 c o n t a i n s the f o l l o w i n g : a) a comprehensive b i l l o f m a t e r i a l s . b) a schedule of i n t e r p h a s i n g , and c) a l i s t i n g o f a p p l i c a b l e drawings and s p e c i f i c a t i o n s . 5. The schedule of i n t e r p h a s i n g r e p r e s e n t s , i n the words of i t s author, "the most important improvement over the run of the m i l l s h o r t c y c l e schedules used today". I t s key f u n c t i o n s i n c l u d e : ' EQUIP- ! MAN- 'QUANTITY MENT POWER : o Z . m m | a o ; a 1 S i n w o - p tn ! m I m | a m f l i d ' n ' T o . 3 : 12 P-- = . « ! • - H 2 , m ; m -<! a 2 =51 Z - * l ts — 1 m i m • 13?' m-i 15; 3-_ I N N -* L A v p . ro _ ^ — M — ? vT» « ~ v O — N) — 0» L i - i ^ N . O ENTER ACTUALS RIGHT OF SLASH O m 9 2 o rn m B •H • rn m o O O a a 2 I §1 a a l l 1> OJ IP A I o O tn ~n ro , ro cn I O O urt ro ro a a> O. CD O u> I O tn y\_ to en O ro Q cn O "•8 o o 8§° i/i tn •n "n ro tn tn -n_-n ro ro ro . O ro cn O O ° tn tn - "n -n ro o 2 O ro -J 8 8 3 o o QUANTITY COMPLETE 2 CO o o z tn z " < * 3 ro _ O tc O ' -* ; z i p * ! -151 re I* : tni I = "-1*1 lis :?r rM o 5-i 2 " "5 c a -f-5 a ! OR l i s > cn c o •-3 C 50 m 2 CD O t-3 33 8 > o i-3 33 P3 8, > EC O I > f M n > CD § s > c > fi < re z rH s o PJ z - 82 -SHIII - APPllCABlf IDDM: AUG 14 B U I 01 M A T I R I A t : DESCRIPTION I A XI EA 5H ELECTRIC CONDUIT 3/4 0 . F 16 INTERNAL TIE RODS SHORING-TUBULAR- 6'H SARMA HORIZONTAL SttOfi. 4X8'X V4" PLYWOOD PULL BOX ELECTRIC CONDUIT 11/2" PULL BOX •A LF EA M QUANTITIES T W TH F M T W TH F' 150 150 150 63 20 IOO 65 100 100 240 150 150 150 400 400 4O0 10 10: AUG 25 SIDE 2 S C H I O U K 01 I N I E H P H A S I N G : ACTIVITES WHICH CONTROL SCHEDULE PROGRESS INTERFERING ACT. TOWER CRANE OPERATIONAL DELIVERY SHORING CITY SERVCES TO BE CONNEC RAMP BY OTHERS XPPHCHBll OWES: I- SC - 4001 ) SC - 4002 V S C - 4003 KOVIRNIHG SPICS: S C - 4 S C - 5 E - I M A B T W T F M T W T F I L 1 SR - WOI \ S n - 5002 I E • 9001 - 9002 PROBLEMS FIGURE 3 WORK INSTRUCTION SHEET BY S. REVAY ( 1 4 ) , MODIFIED BY TURNHAM - 30 -i ) p r o v i d e sub-network schedule without r e q u i r i n g f i e l d s u p e r v i s o r s t o cope wi t h the complexity of a network p l a n ; i i ) f l a g p o s s i b l e problem areas w i t h t r a d e s t o be c o o r d i n a t e d ; and i i i ) f o r c e management t o prepare adequate t r a d e i n t e r f e r e n c e and c o o r d i n a t i o n drawings i n a t i m e l y f a s h i o n . 2 . 2 . 4 D e c i s i o n Support and Expert Systems In t h i s t h e s i s the d i s t i n c t i o n between d e c i s i o n support systems and expert systems i s made as f o l l o w s . "Ordinary x d e c i s i o n support systems' o r g a n i z e knowledge i n data and i n the program, with s p e c i a l i z e d domain s p e c i f i c knowledge i m p l i c i t l y i n c l u d e d i n the program code. In c o n t r a s t , expert systems or g a n i z e knowledge on t h r e e l e v e l s . I n f ormation i s contained i n data, the knowledge base, and the c o n t r o l procedure. T h i s a r c h i t e c t u r e enables expert systems f o r d i f f e r e n t domains t o be e a s i l y constructed."(10) 2 . 2 . 4 . 1 D e c i s i o n Support Systems Gordon Law, i n h i s t h e s i s e n t i t l e d D e c i s i o n Support System f o r  C o n s t r u c t i o n C y c l e Design(8), i d e n t i f i e s f i v e p r o c e s s e s of d e c i s i o n making: - 31 -MODULE -1-PROBLEM RECOGNITION Project TacftnoletY r U . •»<>laa Construct I ox Mjtkodt ,_J_, MODULE - 2 -PROBLEM DEFINITION / Definition of Wilt / D l a n l o n F fe. select Const ruction Technoloolea r ttrottpln*} of Operation* term* MODULE -3-SOLUTION FORMULATION @ ejmurren • •« '< Cycle Tlee ->.( lor te l \ Oml toelleollltlea tot eneource L l a l t t / CreeOef'n / / «»l(M»lt> / I k l t a Knoelot Beta B< DATABASE MANAGEMENT SYSTEM L i l t er A>ellaole Tectiaolaolea / fte.ie. [ Construction V Techno log I** / *e«le> Conatructlon \ Methods toloct froo Stenoera •-•letrloes P r o d ' » i t r Data ease •foduetlr l ty Standards ' Revlee Past •reject Craw Figure 4 Decision Support System Flowchart.  Bv G. Lav (8) - 32 -F i g u r e 5 D e c i s i o n S u p p o r t S y s t e m F l o w c h a r t .  Bv G . Law (8) - 3 3 -1 . p r o b l e m r e c o g n i t i o n , 2 . p r o b l e m d e f i n i t i o n , 3 . s o l u t i o n f o r m u l a t i o n , 4 . s o l u t i o n a n a l y s i s , 5 . d e s i g n i m p r o v e m e n t a n d e n r i c h m e n t . H e t h e n c o n s t r u c t s f i v e m o d u l e s o f a d e c i s i o n s u p p o r t s y s t e m u t i l i z i n g t h e f i v e p r o c e s s e s m e n t i o n e d . T h e g o a l i s t o p r o v i d e t h e c o n s t r u c t i o n m a n a g e r w i t h a d e c i s i o n s u p p o r t s y s t e m f o r t h e d e s i g n o f h i g h r i s e c o n s t r u c t i o n a c t i v i t i e s . T h e f l o w c h a r t f o r t h i s d e c i s i o n s u p p o r t s y s t e m i s r e p r o d u c e d h e r e i n f i g u r e s 4 a n d 5 t o s h o w t h e p r o c e d u r e s u t i l i z e d . M r . L a w g i v e s a v e r y e x t e n s i v e t r e a t m e n t t o t h e t h e o r e t i c a l a s p e c t s o f c y c l e d e s i g n f o r h i g h r i s e c o n s t r u c t i o n u s i n g a c o m p u t e r i z e d f r a m e w o r k ( d e c i s i o n s u p p o r t s y s t e m ) . 2 . 2 . 4 . 2 E x p e r t S y s t e m s A p a p e r e n t i t l e d E x p e r t S y s t e m s f o r C o n s t r u c t i o n P r o j e c t  M o n i t o r i n g ( 1 0 ) , c o m p a r e s e x p e r t k n o w l e d g e b a s e d s y s t e m s t o a l g o r i t h m i c p r o c e d u r e s i n t h e a r e a o f p r o j e c t m o n i t o r i n g a n d c o n t r o l . " W h i l e s o m e p r o j e c t m o n i t o r i n g c a n b e a c c o m p l i s h e d b y a l g o r i t h m i c p r o c e d u r e s , t h e c a p a b i l i t y o f k n o w l e d g e b a s e d e x p e r t s y s t e m s t o d e a l w i t h i l l - s t r u c t u r e d p r o b l e m s a n d t o b e e x t e n s i v e l y m o d i f i e d o v e r t i m e m a k e t h e m d e s i r e a b l e f o r a p p l i c a t i o n i n t h i s a r e a . " - 34 -Knowledge-based expert systems are programs t h a t can undertake i n t e l l i g e n t t a s k s c u r r e n t l y performed by h i g h l y s k i l l e d people. "Expert systems use domain s p e c i f i c knowledge and h e u r i s t i c s t o perform many of the f u n c t i o n s o f a human ex p e r t . The success o f any expert system r e l i e s mainly on the a b i l i t y t o f o r m a l i z e and r e p r e s e n t the knowledge w i t h i n a d i s c i p l i n e . O ften the knowledge i s a c o l l e c t i o n o f s u b j e c t i v e , incomplete, i l l - d e f i n e d , and i n f o r m a l i n f o r m a t i o n . Indeed, a s i d e b e n e f i t o f expert system development i s the formal o r g a n i z a t i o n of i n f o r m a t i o n t h a t was p r e v i o u s l y unexpressed." ( I b i d . p294). Elements o f Ex p e r t Systems There are s e v e r a l components common t o most expert systems. They are: 1. knowledge base; 2. s h o r t term memory; 3. i n f e r e n c e engine; 4. e x p l a n a t i o n module; and 5. knowledge a q u i s i t i o n module. (Ibid.) The knowledge base c o n t a i n s g e n e r a l i n f o r m a t i o n as w e l l as h e u r i s t i c or judgmental knowledge. For r u l e - b a s e d systems, t h i s knowledge can be represented i n the form of IF <condition> THEN <action> r u l e s . Short term memory i s o f t e n r e f e r r e d t o as the f a c t base. T h i s i s a dynamic data base t h a t r e p r e s e n t s the c u r r e n t s t a t e o f the system. As the a c t i o n s of the r u l e s are executed, the f a c t s i n the s h o r t term memory are changed t o r e f l e c t these a c t i o n s . - 3 5 -The i n f e r e n c e engine or executor i s r e s p o n s i b l e f o r the exe c u t i o n of the system through m a n i p u l a t i o n of the r u l e base and the s h o r t term memory. In g e n e r a l , the i n f e r e n c e engine s e l e c t s an " a c t i v e " r u l e (one i n which the premise i s s a t i s f i e d ) and executes the i n d i c a t e d a c t i o n . Three types of i n t e r r e l a t e d components may be used t o l o c a t e a c t i v e r u l e s : i ) A Change Monitor d e t e c t s changes i n the s h o r t memory t h a t may r e q u i r e a t t e n t i o n . i i ) A P a t t e r n Matcher compares the s h o r t term memory with the knowledge base. i i i ) A Scheduler decides which a c t i o n i s the most a p p r o p r i a t e . The e x p l a n a t i o n module. In order f o r the user t o have con f i d e n c e i n any c o n c l u s i o n reached by the expert system, i t i s e s s e n t i a l t h a t the system be capable of e x p l a i n i n g i t s r e a s o n i n g . Thus the e x p l a n a t i o n module i s a very important p a r t of any expert system. The e x p l a n a t i o n module i s not n e c e s s a r i l y a separate e n t i t y . An e x p l a n a t i o n o f the systems' a c t i o n s i s a c t u a l l y c o n t a i n e d i n the r u l e s t h a t are f i r e d . As a minimum, the e x p l a n a t i o n module should be capable of r e p e a t i n g the l a s t r u l e . In r e a l i t y , the system must be abl e t o convince the planner or h i s s u p e r v i s o r as to the reaso n i n g behind any c o n c l u s i o n s g i v e n or the system w i l l not be used. - 36 -The knowledge a c q u i s i t i o n module i s the f i n a l component r e q u i r e d by the expert system. In order t o accomodate the a c q u i s i t i o n of f u t u r e e x p e r t i s e , an expert system should be capable of adding r u l e s t o the knowledge base i n a simple and g r a c e f u l f a s h i o n . Current r e s e a r c h i s attempting t o develop a knowledge a c q u i s i t i o n module t h a t a l l o w s the expert t o b u i l d the knowledge base r a t h e r than r e q u i r e a computer programmer f o r a s s i s t a n c e . P o t e n t i a l Role o f E xpert Systems i n P r o j e c t M o n i t o r i n g Most c o n t r a c t o r s f e e l t h a t computers are not capable of making the s u b j e c t i v e judgments r e q u i r e d throughout the p r o j e c t m o n i t o r i n g p r o c e s s . The reviewed a r t i c l e d i s p u t e s t h i s premise. "While i t i s t r u e t h a t computers cannot s u b s t i t u t e f o r or e l i m i n a t e the need f o r p r o j e c t managers, they can perform beyond t h e i r c u r r e n t a l g o r i t h m i c and a c c o u n t i n g f u n c t i o n s . " ( I b i d . p.297) The f o l l o w i n g items c h a r a c t e r i z e the domain of expert systems: 1. A l g o r i t h m i c methods are e i t h e r not f e a s i b l e , too cumbersome or too r e s t r i c t i v e . 2. There are r e c o g n i z e d experts i n the f i e l d . 3. The t a s k r e q u i r e s from ten minutes to a few days when performed by an expert. 4. The t a s k i s p r i m a r i l y c o g n i t i v e w i t h reasonably h i g h l e v e l concepts or o b j e c t i v e s i n v o l v e d . 5. The t a s k has s u b s t a n t i a l p a y o f f . - 3 7 -Many of the functions of project monitoring f u l f i l l these conditions. Three areas of project monitoring are exceptionally, well suited to the applications of expert systems: cost control, time control, and purchasing and inventory control (Ibid). 2.2.6 Integrated Construction Systems Two a r t i c l e s on the topic of integrated construction systems are b r i e f l y reviewed. The f i r s t , Means Computer Assisted Design and Costing Program - Cad/Cost f l l ) , describes an ex i s t i n g computer ap p l i c a t i o n which integrates design and dra f t i n g with costing. I t u t i l i z e s a CAD (computer aided design system) with a database costing system. Using the features found on a dedicated CAD system such as zoom, rotate, snap and define grids, an object can be drawn. Using the color graphics provided, the estimator can i d e n t i f y areas on the drawing for p r i c i n g . The l i b r a r y feature provides the a b i l i t y to assign and save costs associated with the object. Once an object has been created, and saved, i t may be retrieved and positioned anywhere on the screen. A l l associated l i n e items and costs are automatically applied against the estimate. Upon completion of the design, the costs are fed into an estimating program which calculates costs. I t i s then possible to experiment with a number of alternatives, thus making the planning and design process more productive and e f f i c i e n t , (Ibid p. 25). - 38 -The second a r t i c l e e n t i t l e d I n t e g r a t e d Computer Systems(12), covers a much broader scope of c o n s t r u c t i o n i n f o r m a t i o n system. The paper p r e s e n t s some of the system d e s i g n i s s u e s r e l a t e d t o computer a p p l i c a t i o n s f o r c o n s t r u c t i o n which i n t e g r a t e c o s t , schedule, p r o d u c t i o n c o n t r o l and accounting i n t o u n i f i e d data p r o c e s s i n g a p p l i c a t i o n s . "The c h a l l e n g e i s t o develop and implement a f u l l y i n t e g r a t e d computer system t h a t w i l l p r o v i d e a l l d i s c i p l i n e s w i t h i n s t a n t access t o i n f o r m a t i o n r e q u i r e d f o r making ac c u r a t e and t i m e l y d e c i s i o n s concerning p r o j e c t performance and c o n t r o l . " The f o l l o w i n g l i s t of d i s c i p l i n e s i s g i v e n f o r a c o n s t r u c t i o n o r g a n i z a t i o n : 1. Business management. 2. P r o j e c t management. 3 . S a l e s and marketing. 4 . Design and e n g i n e e r i n g . 5. E s t i m a t i n g . 6. Purchasing. 7. Co n t r a c t a d m i n i s t r a t i o n . 8 . F i e l d c o n s t r u c t i o n . 9. F i n a n c i a l management. These d i s c i p l i n e s are then t a r g e t e d i n the a r t i c l e f o r i n c l u s i o n i n the c o n s t r u c t i o n i n f o r m a t i o n system. - 39 -The paper s i n g l e s out the a c t i v i t y as the b a s i c u n i t of i n f o r m a t i o n p e r t a i n i n g t o a l l d i s c i p l i n e s i n a c o n s t r u c t i o n company. "Each a c t i v i t y f i l e can s t o r e c o s t i n f o r m a t i o n and schedule i n f o r m a t i o n . By combining the c o s t and schedule i n f o r m a t i o n at t h i s l e v e l , the powerful i n t e g r a t i n g of both c o s t and schedule has been achieved." The concept sounds g r e a t . I t s the b i g g e r i s b e t t e r p h i l o s o p h y . However, the author f a i l s t o p o i n t out the down s i d e of c o s t -schedule i n t e g r a t i o n which i s c o m p l i c a t i o n and l o s s of f l e x i b i l i t y . An example of t h i s i n t e g r a t i o n and ensuing l o s s of f l e x i b i l i t y was experienced i n the p r o j e c t d i s c u s s e d i n Chapter 6, The S e a t t l e Subway P r o j e c t . In t h i s case the owner s p e c i f i e d i n the c o n t r a c t t h a t the c o n t r a c t o r s h a l l have the "schedule of v a l u e s " t i e d e l e c t r o n i c a l l y t o the "schedule". The c o n t r a c t o r used a program t h a t had t h i s c a p a b i l i t y . However, problems arose when i t came time t o r e f i n e the schedule. Any a d d i t i o n or d e l e t i o n of an a c t i v i t y would pose an a d d i t i o n a l problem of r e a d j u s t i n g the "schedule of v a l u e s " . Consequently, the main schedule was l a r g e l y f r o z e n and used only where no changes were r e q u i r e d t o the a c t i v i t i e s . Obviously t h i s i s a huge c o n s t r a i n t on the v i a b i l i t y of the s c h e d u l i n g c a p a c i t y . The above problem source can a l s o be d e f l e c t e d away from the computer c a p a b i l i t y and p l a c e d on the l a c k of a b i l i t y of the c o n t r a c t o r , i n t h i s case, t o scope the p r o j e c t c o r r e c t l y i n the f i r s t p l a c e . Having s a i d t h a t , the v i r t u e of f l e x i b i l i t y i n a - 4 0 -c o n t r a c t o r s p l a n n i n g c a p a b i l i t y and i n h i s systems f o r r e p r e s e n t i n g those p l a n s i s i n d i s p u t a b l e . The paper goes on t o d i s c u s s two b a s i c summaries of the a c t i v i t i e s , "summary by job", and "summary by work package". The "job " grouping i s g e n e r a l l y geographic o r s t r u c t u r a l component r e l a t e d . The "work package" i s a breakdown by s u b - c o n t r a c t o r or vendor. These two summaries would form a m a t r i x o f i n f o r m a t i o n i f p l o t t e d one a g a i n s t another. On a c o n c r e t e b r i d g e p r o j e c t , f o r i n s t a n c e , the f o o t i n g s , columns, and beams would be jobs i n the i n f o r m a t i o n summary system. P l a c e rebar, e r e c t forms, and pour c o n c r e t e would be s u b - c o n t r a c t o r or vendor work packages. Both summary c a t e g o r i e s would be u s e f u l t o management. The t o o l f o r c o l l e c t i n g i n f o r m a t i o n f o r the above summaries i s c a l l e d the turnaround document. "The turnaround document p r o v i d e s the data i n p u t v e h i c l e which c r o s s e s the boundary between the f i e l d p r o d u c t i o n and the computerized c o s t and schedule c o n t r o l system." (Ibid) The paper d i s c u s s e s the i n f o r m a t i o n p i e c e s t o be c o l l e c t e d and the importance of the document i n b r i d g i n g the gap between the d a i l y f i e l d work and the accounting system which operates n e c e s s a r i l y on a one or two month delay. A d e s c r i p t i o n of a technique c a l l e d " E xception R e p o r t i n g " i s give n i n which a c t u a l s o f time and c o s t are compared t o estimated time and c o s t s . Those items t h a t are of noteworthy d i f f e r e n c e (eg g r e a t e r than 15% between a c t u a l and estimate) are h i g h l i g h t e d i n the e x c e p t i o n r e p o r t t o management. - 41 -A f i n a l item c o n t a i n e d i n the paper i s a d e s c r i p t i o n o f "performance models". "The budget f o r a p r o j e c t i s a c o s t performance model. The p r o j e c t schedule i s a time performance model. The i n t e g r a t i o n of c o s t and schedule i n f o r m a t i o n a l l o w s the automatic g e n e r a t i o n of many performance models d e r i v e d from these data. These performance models i n c l u d e the c o s t  curve, the p r o d u c t i o n curve, the schedule o f v a l u e s curve, the cash income curve, and the cash requirements curve." (Ibid) The i n t e g r a t e d m o n i t o r i n g of c o s t and schedule a l l o w s these performance models t o be generated as a by-product o f system i n t e g r a t i o n w i t h l i t t l e a d d i t i o n a l i n p u t r e q u i r e d . One l a r g e item of omission i n t h i s paper i s the l a c k of any r e f e r e n c e t o the database u t i l i z e d i n the c o l l e c t i o n o f time and c o s t i n f o r m a t i o n . I t was not made c l e a r how the software allows one t o search the database f o r time or c o s t i n f o r m a t i o n . The a c t u a l i n t e r f a c e between schedule network p r o c e s s o r and database i s not communicated. 2.3 Not Found i n the L i t e r a t u r e The most conspicuous absence i n the l i t e r a t u r e and i n a v a i l a b l e software i s the absence of a d e s c r i p t i o n of the i n t e r f a c e between - 4 2 -"Database" and "Project scheduling" program. In the l i t e r a t u r e , the modules of "Database" and "Schedule" are often included together under the auspices of "Integrated construct ion information systems" but the r e a l i t y of such systems and how they operate, has not been seen. This research points out the need for such a program and of fers a less ambitious s o l u t i o n , Database and Schedule programs running i n p a r a l l e l . Also absent from the l i t e r a t u r e i s any reference to the use of an "off the shelf" database program being used as the environment or framework under which a customized "construction information system" would be developed for use i n heavy cons truc t ion . Lo(9) used t h i s method to develop a construct ion information system a p p l i c a b l e ; f o r r e s i d e n t i a l housing construct ion , but the l o g i c a l extension to heavy c i v i l - s t r u c t u r a l work i s not evident i n the l i t e r a t u r e . F i n a l l y , very l i t t l e was found about the a c t i v i t y design problem and de ta i l ed planning issues . - 4 3 -CHAPTER 3 CONSTRUCTION INFORMATION SYSTEM FORMULATION 3.0 I n t r o d u c t i o n T r e a t e d i n t h i s c h a p t e r i s a s p e c i f i c a t i o n f o r a C o n c r e t e C o n s t r u c t i o n P l a n n i n g S y s t e m w i t h a n i n t e r f a c e t o t h e f u n c t i o n s o f e s t i m a t i n g a n d p r o j e c t c o n t r o l . T h e o b j e c t i v e i s t o s p e c i f y a s y s t e m t h a t w i l l a c c o m o d a t e t h e c o n c e p t u a l a n d p r a c t i c a l a s p e c t s o f c o n c r e t e c o n s t r u c t i o n p r o j e c t p l a n n i n g . 3.1 Work B r e a k d o w n S t r u c t u r e T h e w o r k b r e a k d o w n s t r u c t u r e p r o t o t y p e u s e d i n t h i s t h e s i s o r i g i n a t e d f r o m D a b b a s a n d H a l p i n ( 4 ) a s f o l l o w s : O r g a n i z a t i o n , P r o j e c t , A c t i v i t y , O p e r a t i o n , P r o c e s s , a n d W o r k T a s k . T h i s WBS h i e r a r c h y w a s t h e n m o d i f i e d t o s u i t t h e p e r c e i v e d n e e d s o f r e p e t i t i o u s , c o n c r e t e c o n s t r u c t i o n a s f o l l o w s : - 4 4 -Source L e v e l Example C o n t r a c t o r Owner C o n t r a c t o r C o n t r a c t o r C o n t r a c t o r C o n t r a c t o r C o n t r a c t o r C o n t r a c t o r P r o j e c t D i v i s i o n A c t i v i t y Operation L o c a t i o n L__ Resource D e s c r i p t o r I ~^ Phase Brooklyn B r i d g e Payment c a t e g o r i e s S t r u c t u r a l component eg. beam or f o o t i n g Trade r e l a t e d eg. r e b a r . R e p e t i t i o u s con-s t r u c t i o n address Manpower, Machines, M a t e r i a l s , S u b c o n t r a c t o r s Time, c o s t , Method, d e s c r i p t i o n . B i d estimate, c u r r e n t p l a n , a c t u a l , a r c h i v e F i g u r e 6. Work Breakdown S t r u c t u r e H i e r a r c h y The P r o j e c t , A c t i v i t y , Operation and L o c a t i o n l e v e l s of the h i e r a r c h y are used f o r in-house coding and o r g a n i z a t i o n . The l e v e l of " D i v i s i o n " i s i n s e r t e d f o r the owners' cod i n g and i s not, s t r i c t l y speaking, a l e v e l of the h i e r a r c h y a t a l l but i s i n c l u d e d f o r the owner's convenience. The bottom l e v e l s , Resource, D e s c r i p t o r , and Phase, are l e v e l s or dimensions of m o n i t o r i n g system h i e r a r c h y and are shown as d o t t e d t o d i s c r i m i n a t e from the breakdown r e q u i r e d f o r the p l a n n i n g system h i e r a r c h y . - 4 5 -An " A c t i v i t y " . as used i n the context of t h i s paper, i s usually i d e n t i f i e d as a major s t r u c t u r a l component of the project, eg. a bridge footing, column, or beam. An "Operation" as a breakdown of an a c t i v i t y , i s usually a trade related unit, eg. rebar, formwork, or concrete placement. Operations w i l l often form the basis of work packages for subcontractors and, or vendors. For reasons pertaining to repetitious construction, the breakdown of the a c t i v i t i e s by "Location" i s also used i n t h i s system. The above d e f i n i t i o n for an a c t i v i t y i s not the norm i n the industry. T y p i c a l l y , an a c t i v i t y i s defined as the smallest element of work and involves action. The following i l l u s t r a t i o n shows how t h i s thesis has u t i l i z e d three l e v e l s of hierarchy to more c l e a r l y depict the various aspects of the t y p i c a l a c t i v i t y . This thesis: Typical i n the industry: Component — i Beam Location -> A c t i v i t y 3rd Floor -> Form 3rd f l o o r Beam Operation —I Form These l e v e l s of the work breakdown structure hierarchy are used to create a data structure that w i l l e a s i l y categorize the work breakdown. The advantages to t h i s system w i l l become apparent through the course of t h i s thesis. For each operation on a concrete job, there e x i s t a var i e t y of "Resources" required to complete the work. These resources i n general can be contained in the following headings: - 4 6 -1 . M a n p o w e r 2 . M a t e r i a l s 3 . E q u i p m e n t 4 . M a n a g e m e n t 5 . S u b - c o n t r a c t o r s E a c h o f t h e s e r e s o u r c e h e a d i n g s c o n t a i n s m a n y d i f f e r e n t e l e m e n t s t h a t c o u l d b e c h o s e n , i n v e n t e d , o r o t h e r w i s e p r o c u r e d t o f u l f i l l a r o l e i n t h e c o m p l e t i o n o f t h e w o r k . I n t h e d e s i g n p h a s e o f a p r o j e c t , t h e s p e c i f i c r e s o u r c e s n e e d t o b e s e l e c t e d f o r u s e o n a n a c t i v i t y o r o p e r a t i o n . I n t h e p r o j e c t c o n t r o l p h a s e o f a p r o j e c t , t h e r e s o u r c e n e e d s t o b e a c c o u n t e d f o r . T o d e s c r i b e a n d a c c o u n t f o r t h e a b o v e r e s o u r c e s , p a r a m e t e r s c a l l e d " D e s c r i p t o r s " a r e i n t r o d u c e d t o s t o r e a n d c o l l e c t i n f o r m a t i o n o n t h e v a r i o u s r e s o u r c e s . T h e s e d e s c r i p t o r s f a l l i n t o f o u r c a t e g o r i e s : 1 . T i m e ( d u r a t i o n , p r o d u c t i o n r a t e s , s t a r t / f i n i s h t i m e s ) 2 . C o s t ( e x p e n d i t u r e s , p r o d u c t i v i t y , u n i t c o s t s , e t c ) 3 . D e s c r i p t i o n ( s u p p l i e r , s i z e , a d d r e s s , c o n t a c t , e t c ) 4 . M e t h o d s ( e q u i p m e n t , c r e w c o m p o s i t i o n , m e a n s ) . M e t h o d s a r e f u r t h e r b r o k e n i n t o " d e c i s i o n v a r i a b l e s " t h a t a d d r e s s a l l o f t h e d e c i s i o n s t h a t a r e i n v o l v e d i n m e t h o d d e s i g n . T h e l i s t o f d e c i s i o n v a r i a b l e s f o r m s a c h e c k l i s t o f d e c i s i o n s r e q u i r e d . A n e x a m p l e c h e c k l i s t i s f o u n d i n 4 . 3 . 0 . 1 . - 4 7 -" P h a s e " i s t h e l a s t b r e a k d o w n a n d i t a d d r e s s e s i n f o r m a t i o n s t o r a g e a t p r o m i n e n t s t a g e s o f t h e p r o j e c t , ( b i d e s t i m a t e , c u r r e n t o r f o r e c a s t p l a n , a c t u a l , a n d a r c h i v e . ) T h e w o r k b r e a k d o w n s t r u c t u r e h i e r a r c h y i s m o d e l e d a f t e r t h e T M 1 m u l t i d i m e n s i o n a l h i e r a r c h y c o n t a i n i n g 8 l e v e l s o r d i m e n s i o n s . T h e r e a s o n f o r t h i s i s t h a t c o n s t r u c t i o n i s t r u l y a m u l t i d i m e n s i o n a l r e a l i t y a n d f i t s t h e m o d e l n i c e l y . A l l o f t h e d i m e n s i o n s n e e d n o t b e u t i l i z e d f o r e v e r y a c t i v i t y . B u t t h e s y s t e m h a s b e e n o r g a n i z e d t o p r o v i d e a u n i q u e d a t a b a s e a d d r e s s f o r s t o r i n g p a s t , p r e s e n t , a n d f u t u r e i n f o r m a t i o n , i n o r d e r t o f a c i l i t a t e t h e p l a n n i n g p r o c e s s . T h e f i r s t t a s k o f s y s t e m f o r m u l a t i o n i s t o o u t l i n e t h e s u b -s y s t e m s a n d f u n c t i o n s r e q u i r e d f o r a d e t a i l e d p l a n n i n g s y s t e m . A s s t a t e d i n t h e i n t r o d u c t i o n , t h e c o n s t r u c t i o n s u b - s y s t e m s t h a t a r e c o n s i d e r e d i n t e r r e l a t e d a n d t h u s e s s e n t i a l t o t h e n u c l e u s o f a c t i v i t y p l a n n i n g a r e P r o j e c t c o n t r o l , E s t i m a t i n g , P l a n n i n g , a n d S c h e d u l i n g . T h e s e t h e n f o r m t h e c o r e i n f o r m a t i o n s y s t e m t o w h i c h o t h e r s u b - s y s t e m s c a n b e a d d e d . 3 . 2 M e t h o d o l o g y T h e m e t h o d o l o g y e m p l o y e d f o r t h e i n i t i a l s y s t e m f o r m u l a t i o n i s s i m p l y t o c o n s t r u c t a s p r e a d s h e e t ( f i g u r e 7 ) o f f u n c t i o n s r e q u i r e d b y t h e c o r e s u b - s y s t e m s o f t h e i n f o r m a t i o n s y s t e m . T h e s p r e a d s h e e t l i s t s t h e f u n c t i o n c a t e g o r i e s , f u n c t i o n s , c o m p u t e r - 48 -CONSTRUCTION INFORMATION SYSTEM FORMULATION: SPREAD SHEET OF FUNCTIONS VERSUS ENVIRONMENT AND DATA REQUIREMENTS FI6URE 7 Abreviations: SCH - Scheduling prograi SP SHEET = Spread sheet prograi ii SHEET = Kork sheet TEMPLATE = Foriatted screen Mi th or without data SUM - Suuary f i le TARS ACT DUR = Target activity duration DB - Data base prograi ACT « SHEET = Activity worksheet OPER Ii SHEET = Operation xorksheet ARCH, EDIT - Archive f i l e , edit to suit present project FUNCTION CATEGORY FUNCTIONS ENVIRONMENT DATA ADDITIONAL FILE SOURCE DATA DESTINATION TIME AND COST CONTROL MODULE DATA Daily t i i e sheets ENTRY Purchase orders and invoices DB DB INPUT INPUT OPER FILE OPER FILE PROJECT Operation data collection CONTROL SuMarized project control database Forecasting project costs Monthly payient data structure DB DB DB DB TIME SHEET OPER FILE SUM FILE SUM FILE SUM FILE SUB CONT FILE ARCHIVES Coipany archives of project sunaries DB SUM FILE ESTIMATIN6 AND PLANNIN6 MODULE PROJECT LEVEL PROJECT Project definition input ORGANIZATION Hork breakdonn structure (project) AND Quantity survey spread sheet INPUT Project t i i e constraints and iilestones Schedule: target activity durations PROJ N SHEET INPUT DE 4 SCH ARCK. EDIT SP SHEET ARCH, EDIT DB It SCH INPUT hi SHEET INPUT ACT ii SHEETS ACT Ii SHEETS SCH SCH 4 ACT H SHEE ACTIVITY LEVEL ACTIVITY Activity definition input (identity, constraints and conditions) ACT ti SHEET ARCH, EDIT ORGANIZATION Dork Break-donn Structure. Open a f i l e for each operation ACT H SHEET ARCH, EDIT AND Hierarchical lenus of typical options. OPER H SHEET ARCH, EDIT DESIGN User defined options available OPER H SHEET ARCH, EDIT PARAMETERS Sunarize activity plan. (Decision tree shown) ACT II SHEET FROM ABOVE OPER i SHEET REPETITIOUS Repetitious const, and continuous crew scheduling? If no skip. CONSTRUCTION Standard crew cycle duration: calculation PARAMETERS Unit activity cycle duration: calculation Test for feasibility of standard ere* cycle duration INPUT TARG ACT DUR ACT N SHEET TARG ACT DUR ARCHIVE OPER It SHEET OPER II SHEET OPER H SHEET ACTIVITY SCHEDULING Network Bar chart Line of balance grant) SCH SCH SCH ARCH, EDIT FROM ABOVE FROK ABOVE PRINTOUT PRINTOUT PRINTOUT FIGURE 7 CONTINUES FUNCTION FUNCTIONS ENVIRONMENT DATA ADDITIONAL FILE CATEGORY - SOURCE DATA DESTINATION ACTIVITY Develop cost plans at activity level? If no gc to Operation COST-PLANS Edit activity worksheet to include feasible options (USED NHEN Calculate cost per unit for each feasible option based on: OPERATION Labor, Materials, Equipment, and Sub-contractors REBUIRED) Choose unnui cost option Produce detailed activity design Calculate crew size based on productivity duration Check assuiptions of productivity with selected ere* size Repeat for a l l (detail not required) activit ies ACT H SHEET ARCH, EDIT COST CONTROL COMPUTER AIDED DESIGN PROGRAM OPERATION LEVEL OPERATION Edit operation worksheet to include feasible options LEVEL Calculate controlling resource requireients (ie falsework units) COST-PLANS Obtain design input (ie beai and fori sizing) Calculate cost for each feasible option based on: Labor, Material, Equipient, and Sub-contractors Choose liniiui cost option. List lethods Produce detailed activity design Calculate crew size based on productivity duration Check assuiptions of productivity with selected crew size Repeat for a l l operations of the activity OPER N SHEET ARCH, EDIT COST CONTROL COMPUTER AIDED DESIGN PROGRAM ACTIVITY LEVEL SCHEDULING ANALYSE Coipile histograi of equipient hours CONPOSIT Level equipient resource useage ACTIVITY Update schedules. Check activity duration v target duration Analyse resulting activity plan. Alternatives to explore? Repeat for a l l activities ACTIVITY SCHEDULE FROM ABOVE REFINE PRINTOUT PROJECT LEVEL SCHEDULING. ANALYSIS. AND SUBMITTAL PROJECT Network SCHEDULE Barchart Pert technique Line of balance analysis Contract duration specified? Activity crashing required? PROJECT SCHEDULE FROM ABOVE, REFINE PRINTOUT PROJECT Cash flow RESOURCE Financial analysis USEA6E Manpower Equipient Level project resources TENDER Sub-totals of costs ESTIMATES Overhead, profit, and contingencies Distribute totals aiong pay i te is Calculate unit rates for tender FINISH Tender submitted PROJ SCH FROM ABOVE, OR N SHEET REFINE PROJECT X SHEET OPERATION AND ACTIVITY i SHEETS PRINTOUT PRINTOUT - 5 0 -environments, data sources, and a d d i t i o n a l f i l e data d e s t i n a t i o n s . T h i s then g i v e s an overview of the requirements of the system as a whole. 3.3 F u n c t i o n s Required For The Proposed System For the i n i t i a l system l a y o u t , the spreadsheet i s d i v i d e d i n t o two modules: " P r o j e c t c o n t r o l " which generates time and c o s t i n f o r m a t i o n , and " E s t i m a t i n g , Planning, and S c h e d u l i n g " which r e q u i r e time and c o s t i n f o r m a t i o n . The " f u n c t i o n category" i s i n c l u d e d t o i d e n t i f y and l a b e l f u n c t i o n s of l i k e k i n d . The f u n c t i o n s themselves are the ta s k s t h a t an e s t i m a t o r or planner would pursue enroute t o accomplishing the estimate, p l a n , or schedule. One c o u l d argue t h a t e s t i m a t i n g i s a ta s k much d i f f e r e n t than p l a n n i n g and s c h e d u l i n g . The theory behind combining them i n the same module i s t o t r e a t i t as a two pass module. The f i r s t pass (estimating) r e q u i r e s a broad brush p l a n and schedule t o be able to a s s i g n c o s t s . The second pass (planning and scheduling) r e q u i r e s a d e t a i l e d p l a n and schedule i n order t o minimize c o s t s to be i n c u r r e d . Since the two ta s k s i n c l u d e the same f u n c t i o n s , they are l i s t e d here under one module. For a p r o d u c t i o n system, the e s t i m a t i n g f u n c t i o n would r e q u i r e in-depth d e t a i l . For the purposes of t h i s t h e s i s , e s t i m a t i n g i s co n s i d e r e d c o n c e p t u a l l y and i s i n c l u d e d with p l a n n i n g . - 51 -3.4 C o m p u t e r E n v i r o n m e n t R e q u i r e m e n t s F o r T h e P r o p o s e d S y s t e m T h e a b o v e m e n t i o n e d s p r e a d s h e e t ( f i g u r e 7 ) h a s t h r e e c o l u m n s o n t h e r i g h t o f t h e f u n c t i o n s w h i c h a l l o w t h e s y s t e m d e s i g n e r t o a s s i g n a t t r i b u t e s o f t h e f u n c t i o n s . T h e c o l u m n t i t l e d E N V I R O N M E N T s p e c i f i e s t h e b a s i c c a p a b i l i t y o f t h e c o m p u t e r e n v i r o n m e n t r e q u i r e d b y t h e f u n c t i o n . T h e n e x t c o l u m n , D A T A S O U R C E , s p e c i f i e s t h e o r i g i n o f t h e d a t a r e q u i r e d b y t h e f u n c t i o n . F o r e x a m p l e , t h e f u n c t i o n " D a i l y t i m e s h e e t s " g e t s d a t a f r o m " I n p u t " ( m a n u a l k e y b o a r d i n p u t ) , a n d t h e f u n c t i o n " O p e r a t i o n d a t a c o l l e c t i o n " g e t s d a t a d i r e c t l y f r o m t h e f i l e " D a i l y t i m e s h e e t s " . I n a s i m i l a r m a n n e r , t h e t h i r d c o l u m n , A D D I T I O N A L F I L E D A T A D E S T I N A T I O N S , i d e n t i f i e s f u n c t i o n d a t a o u t p u t w h i c h n e e d s t o b e d i r e c t e d t o a n o t h e r f u n c t i o n . T a k e n a s a w h o l e , t h e s p r e a d s h e e t a l l o w s a v i e w o f s o m e o f t h e s y s t e m f o r m u l a t i o n r e q u i r e m e n t s . I n s u m m a r y , w e n e e d D a t a b a s e , P r o j e c t w o r k s h e e t , S c h e d u l e , Q u a n t i t i y t a k e o f f s p r e a d s h e e t , A c t i v i t y w o r k s h e e t , O p e r a t i o n w o r k s h e e t , a n d C o m p u t e r a i d e d d r a f t i n g a n d d e s i g n c a p a b i l i t i e s . A n a l y s i s o f t h e a b o v e c a p a b i l i t i e s w i t h a l e a s t c o m m o n d e n o m i n a t o r a p p r o a c h y i e l d s a d i v i s i o n o f p r o g r a m e n v i r o n m e n t s t h a t a p p e a r s t o s i m p l i f y t h e s o l u t i o n . T h e u s e o f a d a t a b a s e p r o g r a m i n c o n j u n c t i o n w i t h a s c h e d u l i n g p r o g r a m w i l l p r o v i d e m o s t o f t h e f u n c t i o n a l n e e d s o f t h e s y s t e m . T h e d a t a b a s e w i t h a c u s t o m i z e d p r o g r a m w i l l h a v e t h e c a p a b i l i t y t o s t r u c t u r e t h e - 5 2 -project c o n t r o l , est imating, and planning process with screen prompting and automatic data t rans fer amongst e x i s t i n g f i l e s . The scheduling program w i l l handle the l o g i c a l construct ion sequence, durat ions , s t a r t and f i n i s h times, and w i l l p r o f i l e resources against a c t i v i t i e s . Figure 8 shows the spreadsheet res tructured and sorted by software requirements. I t shows the p a r a l l e l uses of schedule and database functions l i s t e d i n chronologica l order of useage. - 5 3 -MMTCRING AND CONTROL PHASE DATA COLLECTION DATABASE SCHEDULE Daily time sheets -» TO General acxx>unting Weekly time-cost records per activity Summarized act i v i t y cost records Archive of summarized projects Photo or video record of experience Schec iule Summc irized actual schedules Archive of schedules SPREADSHEET ESTIMATING, PLANNING AND SCHEDULING (data manipulation) PHASE PLANNING DATABASE SOFTWARE SCHEDULING SOFTWARE Quantity Survey Spread-sheet •:j>Project organization and input WBS Flow chart for decision sequence WBS Project milestones Target durations Activity organization and input Flow chart of function sequence Decision support system (—> Expert system for each function Hierarchical menus of typical options User defined options available Repetitious construction parameters Standardized crew cycle r> Unit activity duration Test std. cycle duration f e a s i b i l i t y Preliminary schedules Network Barchart Line of balance - 54 -Activity level cost plans (simple activities) or ••Operation level cost plans (choose this level Cffor concrete work and other multiple crew activities) Operation level cost plans Priorize operations to be developed (most complicated or costly first) Retrieve operation worksheet Calculate resource requirements (ie, falsework & formwork required) obtain design input (ie, beam and form sizing) Calculate costs and describe methods labor rates and productivity equipment rates and productivity materials subcontractors total cost and method sunoaxy Repeat for a l l feasible options Choose minhnmi cost option Calculate crew size based on productivity and duration Repeat for a l l operations Activity level Equipment schedules > plot histogram level equip use Activity schedule update •^Activity duration versus target duration Analyze activity plan Analyze resulting activity plan Fil e and print resulting plans Repeat far a l l activities Project level Total costs and final method plans Update project schedules Network Barchart Line of balance Resource levelling - 5 5 -T w o s o l u t i o n s t o t h e s y s t e m d e s i g n p r o b l e m a r e n o w a p p a r e n t . 1 . U t i l i z e a c o m b i n a t i o n o f c o m m e r c i a l d a t a b a s e , s c h e d u l i n g , a n d s p r e a d s h e e t p r o g r a m s . 2 . W r i t e a p r o g r a m t h a t w o u l d c o m b i n e t h e c a p a b i l i t i e s o f a d a t a b a s e p r o g r a m , s c h e d u l i n g p r o g r a m , a n d s p r e a d s h e e t u s i n g a l a n g u a g e l i k e B a s i c , C , o r P a s c a l . W h i l e t h e s e c o n d s o l u t i o n w o u l d p r o v i d e a n i n t e g r a t e d s y s t e m w i t h t h e a d v a n t a g e s o f s i n g l e d a t a e n t r y a n d i n t e r c h a n g e a b l e f i l e s b e t w e e n s c h e d u l i n g a n d d a t a b a s e , t h i s a l t e r n a t i v e i s c o n s i d e r e d b e y o n d t h e s c o p e o f t h i s r e s e a r c h . 3 . 5 A P r o p o s e d S y s t e m I n T w o P a r t s : T h e 8 0 % S o l u t i o n . T h e p r o p o s e d s o l u t i o n e v o l v e s f r o m t h e o b s e r v a t i o n t h a t s c h e d u l i n g a n d d a t a b a s e p r o g r a m s p r e s e n t l y e x i s t o n t h e m a r k e t w h i c h a r e e x t r e m e l y s o p h i s t i c a t e d i n t h e i r o w n r i g h t . P r e s e n t d a y c o n s t r u c t i o n m a n a g e m e n t r e q u i r e s b o t h o f t h e s e f u n c t i o n s a n d t h i s r e s e a r c h e x a m i n e s t h e m e r i t o f c r e a t i n g a n d m a i n t a i n i n g p a r a l l e l s c h e d u l i n g a n d d a t a b a s e p r o g r a m s w i t h i n t h e c o n t e x t o f o n e i n f o r m a t i o n s y s t e m . T h e s e s y s t e m s c o u l d p o s s i b l y s h a r e i n f o r m a t i o n f i l e s b u t t h i s i s u n l i k e l y w i t h o u t a c o n c e r t e d e f f o r t f r o m a s o f t w a r e h o u s e t h a t w o u l d d e v e l o p b o t h p a c k a g e s . L a c k i n g t h e a b i l i t y t o s h a r e f i l e s , t h i s s o l u t i o n f o r c o n s t r u c t i o n s y s t e m s w o u l d o n l y b e o n t h e o r d e r o f 80% e f f i c i e n t w h e n c o m p a r e d t o a c o m p l e t e l y i n t e g r a t e d s y s t e m . - 5 6 -The reason for the design of a system with two p a r a l l e l software programs i s the conceptual s i m p l i c i t y of the two system approach. By separating (1. scheduling) from (2. estimating, planning, and project co n t r o l ) , one can e a s i l y follow the l o g i c required to construct the system modules. 3.6 P l a n n i n g Models Thus far i n Chapter 3 , the emphasis has been on the requirements of the information system i n terms of functions, environments, and s p e c i f i c software. We w i l l now focus on a system that w i l l aid i n estimating, planning, and project control with emphasis on planning of projects and a c t i v i t i e s within projects. The name selected for t h i s planning vehicle i s the "planning  model" or the "planning algorithm". A planning model i s defined  to be step by step guideline for developing a construction  methods plan for a project and the a c t i v i t i e s within that  project. The most suitable environment for the planning model as mentioned e a r l i e r i s commercially available database software. The planning model database system provides the following features: - 5 7 -1. A c o n c e p t u a l a n d c o m p u t a t i o n a l f r a m e w o r k u p o n w h i c h t o o r g a n i z e a n d s e q u e n c e t h e m o d u l e s a n d f u n c t i o n s t h a t m a k e u p t h e c o n s t r u c t i o n i n f o r m a t i o n s y s t e m . M e n u d r i v e n p r o m p t i n g p r o v i d e s o r d e r f o r t h e i n c l u d e d f u n c t i o n s . 2 . A d a t a s y s t e m w h i c h c o l l e c t s , s o r t s , a n d p e r f o r m s a r i t h m e t i c o p e r a t i o n s o n c o n s t r u c t i o n i n f o r m a t i o n . I t w i l l h a v e t h e p r o g r a m m e d c a p a b i l i t i e s o f a u t o m a t i c d a t a t r a n s f e r f r o m t i m e c a r d f i l e t o p r o j e c t d a t a f i l e a n d e m p l o y e e p a y r o l l f i l e . T h e a b i l i t y t o c o n d e n s e t h e p r o j e c t d a t a f i l e t o a s u m m a r y f i l e f o r a n a l y s i s a n d a r c h i v i n g w i l l a l s o b e a v a i l a b l e . 3 . A d e c i s i o n s u p p o r t s y s t e m t h a t p r o m p t s t h e u s e r t h r o u g h t h e m o d u l e o r f u n c t i o n i n q u e s t i o n . B y u s e o f c u s t o m i z e d p r o g r a m m i n g i n t h e d a t a b a s e l a n g u a g e , d e c i s i o n s u p p o r t i s a v a i l a b l e w h i c h w i l l s e q u e n c e t h e o r d e r o f d e c i s i o n s t o b e m a d e , a n d g i v e h i s t o r i c a l d a t a f r o m p r e v i o u s p r o j e c t d a t a f i l e s a n d s u p p l y c o n s t r u c t i o n t e c h n o l o g y i n f o r m a t i o n p e r t i n e n t t o c o n c r e t e c o n s t r u c t i o n . F r o m t h i s d a t a , a p p r o p r i a t e p r o d u c t i o n r a t e s , c y c l e d u r a t i o n s , c o s t s p e r u n i t , e t c . c a n b e s e l e c t e d f o r t h e c o n s t r u c t i o n d e s i g n p r o b l e m a t h a n d . I n e s s e n c e , a p l a n n i n g m o d e l i s f i r s t a m e n u f o r a c t i v i t y p l a n n i n g , s e c o n d a s t o r a g e v e h i c l e f o r a s s e m b l e d p l a n s , a n d t h i r d a d a t a b a s e o f c o l l e c t i v e c o m p a n y e x p e r i e n c e f o r v a r i o u s c o n s t r u c t i o n m e t h o d s , c o s t s , t e c h n i q u e s , m a t e r i a l s , t i m e d u r a t i o n s , a n d e q u i p m e n t . - 5 8 -The p l a n n i n g model u t i l i z e s i n f o r m a t i o n from s c h e d u l i n g software i n c l u d i n g c r i t i c a l path method output of b a r c h a r t s , network diagrams, and l i n e of balance diagrams. I t a l s o a s s i m i l a t e s a c c o u n t i n g data such as job c o s t data, p r o d u c t i v i t y and l a b o u r r a t e s , and p r o d u c t i o n r a t e s . F i n a l l y i t c o l l e c t s c o n s t r u c t i o n technology i n f o r m a t i o n and p r o v i d e s an advantageous c l i m a t e t o p l a n and monitor the c o n s t r u c t i o n p r o j e c t . 3.6.1 B e n e f i t s o f U s i n g P l a n n i n g Models S i m i l a r problems t h a t r e o c c u r f r e q u e n t l y are common i n e n g i n e e r i n g . These problems are u s u a l l y handled by d e v e l o p i n g g e n e r a l formulae and methods of s o l u t i o n so t h a t the problem s e t -up time i s minimized. The a c t i v i t y p l a n n i n g problem being s t u d i e d i n t h i s t h e s i s i s of t h i s nature. For a b r i d g e c o n t r a c t i n g company, the a n a l y s i s and d e s i g n of each b r i d g e c o n s t r u c t i o n a c t i v i t y w i l l occur each time a p r o p o s a l i s made or a c o n t r a c t i s won. By u s i n g a p r e v i o u s l y developed p l a n n i n g model t o a i d i n the a c t i v i t y design, savings of time and money can be r e a l i z e d by s u b s t a n t i a l l y r e d u c i n g the d u p l i c a t i o n of work common t o a l l b r i d g e p r o j e c t s . At the same time, the o p p o r t u n i t y to e x p l o r e more s t r a t e g i c a l t e r n a t i v e s i n a t i m e l y and economical way i s an a d d i t i o n a l b e n e f i t . - 59 -3.6.2 G r a p h i c a l Techniques The model uses a variety of graphical techniques to aid i n the understanding of c e r t a i n concepts. These i l l u s t r a t i o n s give excellent conceptual c l a r i t y and allow instant recognition of trends i n the solution. Techniques such as work breakdown structure, precedence networks, barcharts, decision trees, time-space diagrams, and resource histograms are used throughout the model. 3.6.3 The Models Presented This thesis presents research on two s i m i l a r transportation corridor construction projects and develops a planning model which, because of i t s generic approach, i s suitable for both construction projects. The research was done sequentially. F i r s t , a planning model was developed for concrete, c a s t - i n -place, multispan, bridge construction. At a l a t e r date, the bridge construction planning model was tested on a cut and cover tunnel project, and modified to s u i t the application of a tunnel project. The issue of t r a n s p o r t a b i l i t y of the model from one kind of construction project to another i s of i n t e r e s t . The tradeoff always exists between s p e c i f i c and generic systems. The s p e c i f i c i s immediately appropriate and useable, but narrow in the scope i t addresses. While the generic needs to be t a i l o r e d to the - 6 0 -application to a certain degree p r i o r to coining on l i n e , but i t addresses the basic requirements of a l l projects involving concrete construction. Application i n the re a l world i d e a l l y would begin with the generic model. Save i t . T a i l o r the model to a s p e c i f i c a p p l i c i c a t i o n such as a bridge. Save i t . When the next project comes along, use the model which most c l o s e l y addresses the needs of the new project. Modify the model again, and so on. The need for f l e x i b i l i t y has thus been addressed. The model needs to be i n such a form that i t can be e a s i l y changed to address d i f f e r e n t procedures or requirements that w i l l i nevitably occur from project to project. - 61 -CHAPTER 4. THE GENERAL PLANNING MODEL FOR CONCRETE CONSTRUCTION 4.0 I n t r o d u c t i o n The "General Planning Model" p r o v i d e s a sequence of d e s i g n f o r a g e n e r i c c o n c r e t e c o n s t r u c t i o n p r o j e c t c o n t a i n i n g a c t i v i t i e s and o p e r a t i o n s . The model f o l l o w s the work breakdown s t r u c t u r e h i e r a r c h y . Through the process i t serves as the framework prompting the us e r through the d e s i g n process, the data system c o l l e c t i n g and r e t r i e v i n g p r o d u c t i o n r a t e s , u n i t c o s t s , e t c , and the d e c i s i o n support system f o r the p r o j e c t and a c t i v i t y d e s i g n problem. Si n c e a model without a context can become ve r y a b s t r a c t and hard t o p i c t u r e , t h i s t h e s i s has developed a worked example, the "Beam C o n s t r u c t i o n " a c t i v i t y of a multispan, p o s t - t e n s i o n e d b r i d g e p r o j e c t . As mentioned i n Chapter 3, s p e c i f i c p l a n n i n g models would be d e r i v e d from the gen e r a l model by t a i l o r i n g the model t o the p r o j e c t a t hand. The Concrete Bridge P r o j e c t Example i s i n c l u d e d f o r c l a r i t y and can be thought of as a the r e s u l t of a s p e c i f i c p l a n n i n g model. The beam c o n s t r u c t i o n a c t i v i t y i s s e l e c t e d because i t i s the most complicated of the b r i d g e p r o j e c t a c t i v i t i e s . The g e n e r a l p l a n n i n g model i s i s t h e r e f o r e demonstrated w h i l e a d d r e s s i n g the requirements of the most complicated a c t i v i t y . - 62 -4.0.1 General Planning Model Flow Chart The General Planning Algorithm proposed i n t h i s paper i s presented i n flow chart form i n figure 9. This flow chart c l e a r l y shows the step-by-step procedure to follow for planning the construction of the r e p e t i t i v e a c t i v i t i e s and i s a very useful t o o l to aid i n the understanding of the model. By using t h i s chart, i t i s r e l a t i v e l y easy for one to grasp the method of solution without becoming l o s t i n the d e t a i l e d requirements at each step. 4.0.2 Example Overview: f^inhip. Bridge Vancouver. BC. The City of Vancouver i n B r i t i s h Columbia, Canada, decided to replace the ageing Cambie Bridge with a six lane, concrete structure spanning a 250 metre waterway and with a t o t a l length of 1 kilometre. The bridge design by N.D. Lea & Associates and modified by Stephenson Construction c a l l e d for a central post-tensioned spine beam to be cast i n place with the remaining width to be cast l a t e r with a t r a v e l l i n g "wing" form. The centre span was 8 0 meters between columns and a 50 meter length was precast on a barge and l i f t e d into place. The remaining 40 spans were formed on falsework approximately 10 metres above the ground, one span at a time. These r e p e t i t i v e spans and the plan for the a c t i v i t y of bridge beam construction are the focus of t h i s planning model. 1.1 1 P R O J E C T - CONCRETE B R I D G E P R O J E C T L E V E L P l a n s S p e c i f i c a t i o n s O t h e r C o n t r a c t D o c u m e n t s 1 . 2 P R O J E C T W o r k B r e a k d o w n S t r u c t u r e 1 . 3 P r o j e c t C o n s t r a i n t s 1 . 5 t  MODEL THE P R O J E C T N e t w o r k B a r c h a r t T a r g e t D u r a t i o n s " . Q U A N T I T I E S R A T E T A B L E S NO ! C h e c k T a r g e t D u r a t i o n V e r s u s C o n t r a c t D u r a t i o n 1 . 8 H a v e Now S a t i s f i e d t h e P r o j e c t C o n s t r a i n t s , M i l e s t o n e D a t e s , E t c . , a n d H a v e E s t a b l i s h e d " T a r g e t " A c t i v i t y D u r a t i o n s a n d P r o d u c t i o n R a t e s . F i g u r e 9 G e n e r a l P l a n n i n g Mode l F l o w c h a r t 1 ?,1 C R E A T E A N D D E F I N E A C T I V I T Y 1 . A c t i v i t y U B S 2 . D i c t i o n a r y + C o d i n g 3. A c t i v i t y D e c i s i o n T r e e A C T I V I T Y L E V E L 2.2 .. T MODEL THE A C T I V I T Y 1 . N e t w o r k 2 . B a r c h a r t 3 . T i m e - S p a c e S c h e d u l e ( D e f i n e C r e w O p e r a t i o n s ) I N P U T L I N E A R C O N S T R A I N T S 1 . C h o o s e E q u a l D u r a t i o n s f o r E a c h " C r e w O p e r a t i o n ' 2 . C a l c u l a t e U n i t A c t i v i t y C y c l e D u r a t i o n . 2 . 5 SORT A C T I V I T Y I N T O 1 . I n d e p e n d e n t 2 . I n t e r d e p e n d e n t ( i e : f a l s e w o r k s y s t e m ) 3. P r i o r i z e A c c o r d i n g t o E x p e c t e d I m p a c t 1 FROM ACTIVITY. LEVEL RESULTS PREVIOUS JOB RECORDS J U I CREATE OPERATION WORKSHEET For A l l Operations COPY FEASIBLE OPTIONS For Each Operation CALCULATE SPECIFIC RESOURCE  REQUIREMENTS ~ To Meet the "target" Production Rate. ( I e . # of spans o f falsework 3.3 OBTAIN DESIGN INPUT 1. Falsework; Forms 2 . Temporary Foundations 3. Specia l T r a v e l l e r Forms ( s i z e s , spacings, e t c . ) 3.4 CALCULATE COST/SPAN FOR EACH F E A S I B L E OPERATION OPTION USING: 1. Labor P r o d u c t i v i t y /Span 2. Eouip. P r o d u c t i v i t y /Span 3. Mater ia l costs / span 3.5 LAST OPTION NO F i g u r e 9 C o n t i n u e d 1 OPERATION LEVEL ( x« CHOOSE MINIMUM COST OPTION 3.6 CREW SIZE 1. Calcu la te Crew Size Based on P r o d u c t i v i t y + Crew Cycle Duration 2 . Check Assumptions o f Prod wi th Selected Crew S i z e 4.1 ' V t S CONSIDER MAJOR EQUIPMENT 1. Equip. Hours for Each Operation 2. Resource Histogram 3. Modify Operation Duration: to Suit Levelling Req'd. 4.2 ACTIVITY LEVEL RESULTS UPDATE • CHECK ACTIVITY SCHEDULE CPU Network Barchart Time-Space Schedule 4.3 PRELIMINARY DESIGN OF ACT."I' IS COMPLETE"  TABULATE RESULTS: - men - machines - money - schedule - method - assumptions - materials CHECK PROJECT SCHEDULE 1. Logic network 2. Barchart ! F i g u r e 9 C o n t i n u e d HO NEXT ACTIVITY YES 5.4 I CRASH SOME CRITCAL ACTIVITIES 1. Estimate Crash Cost 2. Priorlze Crit. Act. by Mln. Cost/Day to Crash 3. Choose an Activity or Combination to Crash 4. CRASH 5.5 131 I Schedule  Costs ~] Materials i _ ipment I _J Manpower - 66 -4.1 P r o j e c t L e v e l : Commencement o f the P l a n While the p l a n n i n g a l g o r i t h m focuses on the a c t i v i t y and o p e r a t i o n l e v e l s of p l a n n i n g , t h e r e are p r o j e c t l e v e l i n p u t s r e q u i r e d f o r the p l a n n i n g p r o c e s s . The p l a n n i n g a l g o r i t h m begins w i t h these i n p u t s . 4.1.0 The E stimate The b u l k of the elements t h a t are r e q u i r e d f o r e s t i m a t i n g are the same as those r e q u i r e d f o r p l a n n i n g . A l i s t o f elements common to both i s as f o l l o w s : q u a n t i t y t a k e o f f , method p l a n , p r o d u c t i v i t y r a t e s (Manhours / u n i t ) a p p l i c a b l e t o the method s e l e c t e d , l a b o r and equipment r a t e s . The f o l l o w i n g are elements t h a t would not n e c e s s a r i l y be i n v o l v e d a t the p l a n n i n g l e v e l but would be r e q u i r e d f o r the estimate: i n f l a t i o n adjustment, mark-up and p r o f i t , economic, and p o l i t i c a l f a c t o r s t h a t might a f f e c t the b i d p r i c e . 4.1.1 Proj e c t Award The f o l l o w i n g p r o j e c t s p e c i f i c parameters are g i v e n f o r the a c t i v i t y p l a n n i n g example of "Beam c o n s t r u c t i o n " . - 67 -Concrete Bridge: multi-span, cast-in-place, using post-tensioned and mild s t e e l reinforcement. Number of adjacent ramps: 2 Number of spans: 19 x 2 = 38 Number of beams/span: 1 Milestone completion date: 40 weeks = 200 working days 4.1.2 P r o j e c t Work Breakdown S t r u c t u r e (WBS) A work breakdown structure i s developed by subdividing the project into construction components as shown i n the t y p i c a l bridge section i n figure 10. Each component w i l l require i t s own construction methods, manpower, materials, equipment, etc., and i s defined as an a c t i v i t y (see 3.1) An example WBS example i s displayed i n figure 11 to provide a prototypical bridge project against which the planning model presented herein may be applied and tested. - 68 -PILES LIGHTING OVERLAY HANDRAILS BARRIERS + FASCIA DECK BEAM COLUMN FOOTING DRAINAGE EXCAVATION F igure 1 0 S e c t i o n Through a Typ ica l Concrete Br idge Showing The A c t i v i t y and P ro jec t Level WBS Elements" - 69 -Proj e c t L e v e l A c t i v i t y L e v e l O p e r a t i o n L e v e l Concrete Bridge P i l e s E x c a v a t i o n and b a c k f i l l F o o t i n g s Columns Abutments Drainage Beams Deck B a r r i e r s Overlay H a n d r a i l s L i g h t i n g and e l e c t r i c a l Shore f o o t i n g s Shore towers Prefab forms E r e c t towers Free form Rebar placement P o s t - t e n s i o n d u c t i n g Concrete and cure P o s t - t e n s i o n s t r e s s i n g Form removal F i g u r e 11 Example WBS For A Concrete Bridge P r o j e c t 4 . 1 . 3 P r o j e c t C o n s t r a i n t s Next, the p r o j e c t c o n s t r a i n t s must be l i s t e d . (e.g. mile s t o n e dates, d i f f i c u l t geometric shapes, h e i g h t o f s t r u c t u r e above ground, s i t e area a v a i l a b l e , expected weather c o n d i t i o n s , e t c . ) . T h i s i n f o r m a t i o n w i l l be r e q u i r e d when a s s e s s i n g the c o m p a r a b i l i t y of the h i s t o r i c a l p r o j e c t s summarized i n the database wi t h the present p r o j e c t . As w e l l , the c o n s t r a i n t l i s t w i l l b egin t o focus the d e s i g n e r ' s a t t e n t i o n on a v a i l a b l e methods of c o n s t r u c t i o n . - 7 0 -4.1.4 Q u a n t i t y T a k e o f f and Rate T a b l e s C a l c u l a t i o n of the number of u n i t s of primary m a t e r i a l s t o be used i n the c o n s t r u c t i o n o f each a c t i v i t y i s r e q u i r e d f o r the estimate and subsequent p l a n n i n g . ( i . e . m2 formwork, m3 c o n c r e t e , kg rebar, kg p . t . tendon, e t c . ) . These v a l u e s w i l l be used l a t e r i n c o n j u n c t i o n w i t h p r o d u c t i v i t y i n f o r m a t i o n t o determine p r o d u c t i o n c o s t e s t i m a t e s . Rate t a b l e s l i s t i n g c u r r e n t t o t a l c o s t s per manhour, or per equipment-hour, are in p u t f o r a l l t r a d e s and f o r a l l f e a s i b l e equipment r e q u i r e d by the p r o j e c t . 4.1.5 Model The P r o j e c t F i g u r e 12 shows an example precedence network f o r a concrete b r i d g e w i t h the l o g i c between a c t i v i t i e s shown. At t h i s p o i n t , the a c t i v i t y d u r a t i o n s are not y e t known as the c o n s t r u c t i o n methods f o r each a c t i v i t y have y e t to be determined . Ta r g e t D u r a t i o n s When c o n s t r a i n e d by c o n t r a c t m i l e s t o n e s , i t i s sometimes u s e f u l t o know the d u r a t i o n time a v a i l a b l e f o r lengthy a c t i v i t i e s . To do t h i s one can o b t a i n " t a r g e t d u r a t i o n s " . SS=5 0 START SS=2 SS=4 CONCRETE BRIDGE PROJECT PRECEDENCE NETWORK SS=12 SS=10 SS=10 FS=1 0 b / 11 PILES EXCAVATE FOOTINGS NORTH ABUT. B.FILL D.=12 SS=5 24 BEAMS L U v z v FS=0 FF = 13 COLUMNS SOUTH ABUT. 36 DECK AM 46 5 6 BARRIERS 3VERLAY HAND-RAILS .,,,12 3 M 196 200 FF=12/ \FF=10 / V\FF SS=1 ~ 3 / FF=7 LIGHT-ING SS = 10 PRELIMINARY EARLY START AND -LATE FINISH DATES FOR TARGET DURATION CALCULATIONS. FORM FABRIC-ATION DECk FORM FABRICA! TION LEGEND : ESD kCTIVITTf LFD TIME IN DAYS i Figure 12 Precedence Network f o r a Concrete Bridge P r o j e c t w > M U < PILES CONCRETE BRIDGE PROJECT  BARCHART SCHEDULE  TARGET DURATIONS •EXCAVATION , BACKFILL//, FOOTINGS ABUT f i t A L E G E N D COLUMNS / / / / / / ABUT. DRAINAGE TARGET DURATION FROM PREV.RECORDS 21 (DURATION LESS THAN MAXIMUM DURATION) TARGET DURATIONS = MAXIMUM MINUS CONTENGENCY MAXIMUM DURATION = T -T - T cont r a c t p r e d i c e s s o r successor > LATE FINISH DATES B E A M S TARGET DURATION • 30 weeks • \ D E C K S B A R R I E R S EARLY START DATES ///////// O V E R L A Y /* / 4 f / / /• L I G H T I N G / / / / / / / / / A-A T I M E DURATION CONTENGENCY T 1 1 r- - i — I — i — r 10 i — i — r i — r ' I ' 20 Contract Duration, T 1 r 15 l—i—r -J-T 25 1—r 30 T — i — i — r T — r 35 T I 40 contract = 4 0 w e e k s = 2 0 0 d a y s Figure 13 Barchart Schedule Showing A c t i v i t y Target Durat ions - 73 -Target d u r a t i o n = c o n t r a c t d u r a t i o n minus (preceding a c t i v i t y l e a d time p l u s subsequent a c t i v i t y d u r a t i o n s ) . The assumption r e q u i r e d here i s t h a t the l e a d i n g and l a g g i n g a c t i v i t y d u r a t i o n s as roughly estimated above are of the c o r r e c t or d e r of magnitude t o y i e l d a dependable r e s u l t . For r e p e t i t i o u s c o n s t r u c t i o n t h i s i s o f t e n not an unreasonable assumption. The example p r e l i m i n a r y b a r c h a r t f o r t a r g e t d u r a t i o n s ( f i g u r e 13) shows t h a t the e a r l y a c t i v i t i e s are o n l y on the c r i t i c a l path f o r the f i r s t one or two u n i t a c t i v i t i e s . L ikewise, the l a t e a c t i v i t i e s are o n l y on the c r i t i c a l path f o r the l a s t one or two u n i t a c t i v i t i e s . The time remaining between e a r l y and l a t e a c t i v i t i e s p l o t t e d i n t h i s manner i s the remaining d u r a t i o n f o r the lengthy a c t i v i t y . P r o j e c t Bar Chart An estimate of each a c t i v i t y d u r a t i o n can be made by t a k i n g the product of the average u n i t a c t i v i t y d u r a t i o n s from the p r e v i o u s job r e c o r d s and the number of u n i t s of a c t i v i t y r e q u i r e d f o r the p r e s e n t p r o j e c t . A f a c t o r f o r d i f f i c u l t y can be c o n s i d e r e d i n t h i s p r o c e s s . These d u r a t i o n s are then p l o t t e d w i t h o v e r l a p p i n g to form a bar c h a r t and are r e f e r r e d t o as p r e l i m i n a r y i n i t i a l d u r a t i o n s or " t a r g e t d u r a t i o n s " . Target d u r a t i o n s are u s e f u l i n t h a t they p r o v i d e a s t a r t i n g p o i n t f o r e s t i m a t i n g d u r a t i o n . T a r g e t d u r a t i o n s allow the planner an overview of d u r a t i o n s p r i o r to d e t a i l e d a c t i v i t y design. - 74 -4.1.6 C o n t r a c t D u r a t i o n S p e c i f i e d ? I f c o n t r a c t d u r a t i o n (T c o n t r a c t ) i s s p e c i f i e d , one needs t o check t h a t the t a r g e t p r o j e c t d u r a t i o n i s l e s s than the c o n t r a c t d u r a t i o n . I f T c o n t r a c t i s not s p e c i f i e d , go t o 4.2. 4.1.7 P r o j e c t T a r g e t D u r a t i o n v s . C o n t r a c t D u r a t i o n The p r o j e c t t a r g e t d u r a t i o n i s now compared t o the c o n t r a c t d u r a t i o n . I f the t a r g e t d u r a t i o n i s s i g n i f i c a n t l y l e s s than the c o n t r a c t d u r a t i o n , then t h i s f a c t i s t o be noted. C e r t a i n a c t i v i t i e s c o u l d be lengthened i n d u r a t i o n i f a r e d u c t i o n i n c o s t c o u l d then be r e a l i z e d . I f the p r e l i m i n a r y t a r g e t d u r a t i o n i s s i g n i f i c a n t l y g r e a t e r than the c o n t r a c t d u r a t i o n , then the c o n t r a c t d u r a t i o n w i l l d i c t a t e the f i n a l t a r g e t d u r a t i o n s t o be used ( i e : the time consuming a c t i v i t i e s w i l l r e q u i r e s h o r t e n i n g ) . F i g u r e 13 shows an example b a r c h a r t c o n s t r u c t e d t o show t a r g e t d u r a t i o n s f o r the a c t i v i t i e s of a t y p i c a l b r i d g e p r o j e c t . The a c t i v i t i e s shown c r o s s hatched are on the c r i t i c a l path f o r only one or two u n i t a c t i v i t i e s and are t h e r e f o r e not candidates f o r r e d u c i n g the p r o j e c t d u r a t i o n . Those a c t i v i t i e s shown shaded are on the c r i t i c a l path f o r t h e i r e n t i r e d u r a t i o n . For the th r e e a c t i v i t i e s shown i n the example, the e a r l y s t a r t date minus the l a t e f i n i s h date y i e l d s the maximum d u r a t i o n . The t a r g e t - 75 -d u r a t i o n i s then found by s u b t r a c t i n g a contingency f a c t o r from the maximum d u r a t i o n . One would note f o r these a c t i v i t i e s t h a t the t a r g e t d u r a t i o n may not be s i g n i f i c a n t l y exceeded. Beam example: T a r g e t D u r a t i o n p r e v i o u s r e c o r d s i n d i c a t e 4.6 days per span * 38 spans Target D u r a t i o n = 175 Days C o n t r a c t D u r a t i o n = 200 Days Tmax = ( T c o n t r a c t - Tpredecessor - Tsuccessor) = 160 days, Use t a r g e t d u r a t i o n = 150 days. A c t i v i t y P r o d u c t i o n Rate A c t i v i t y P r o d u c t i o n Rate = # of u n i t a c t i v i t i e s t a r g e t a c t i v i t y d u r a t i o n # of spans 38 spans Beam Pr o d u c t i o n Rate = = t a r g e t d u r a t i o n 150 days Beam P r o d u c t i o n Rate = 0.253 beams/day. - 76 -This i s a " b a l l park" minimum production rate since "beams" are on the c r i t i c a l path and the contract duration governs the project duration. 4.2 A c t i v i t y L e v e l P l a n n i n g 4.2.1 Create and Def i n e t h e A c t i v i t y Commencement of the A c t i v i t y Level analysis begins with "Create WBS", "Create Dictionary and Coding System", and "Create A c t i v i t y Decision Tree". Existing, standardized records w i l l be u t i l i z e d for these procedures. Modifications to the e x i s t i n g records w i l l then be made to s u i t the present a c t i v i t y being considered. Work Breakdown Structure (WBS) This i s a graphical representation of the a c t i v i t y subdivided into the basic operations that comprise the a c t i v i t y . An example A c t i v i t y WBS for Beam Construction i s shown below. - 77 -Beam C o n s t r u c t i o n Shore f o o t i n g s Shore towers Prefab forms E r e c t towers Free form Rebar placement P o s t - t e n s i o n d u c t i n g Concrete and cure P o s t - t e n s i o n s t r e s s i n g Form removal F i g u r e 14 Example WBS For Beam C o n s t r u c t i o n C y c l e D i c t i o n a r y and Coding A l l elements of the WBS must be c l e a r l y d e f i n e d and coded wi t h r e s p e c t t o the company's e s t a b l i s h e d . A c t i v i t y D e c i s i o n Tree T h i s i s a g r a p h i c a l technique used t o r e p r e s e n t a l t e r n a t i v e methods ( a l s o c a l l e d method options) f o r a l l o p e r a t i o n s of an a c t i v i t y . I t i s a u s e f u l technique w i t h which t o v i s u a l i z e the a c t i v i t y as a whole and to see the range of method o p t i o n s f o r each o p e r a t i o n of the a c t i v i t y . I t i s an e x t e n s i o n of the work breakdown s t r u c t u r e . The d e c i s i o n t r e e forms a h i e r a r c h y of d e c i s i o n s t o be made f o r the s e l e c t i o n and des i g n of method o p t i o n s . F i g u r e 15 shows an example d e c i s i o n t r e e f o r beam c o n s t r u c t i o n . In the pr o c e s s of developing the d e c i s i o n t r e e , some of the dependencies between o p e r a t i o n s w i l l become obvious. For - 7 8 -i n s t a n c e , s t r i p p i n g i s a f u n c t i o n of forming system. These two o p e r a t i o n s w i l l l a t e r be combined f o r the d e s i g n p r o c e s s . The d e c i s i o n t r e e has helped with the v i s u a l i z a t i o n and o r g a n i z a t i o n p r o c e s s . 4.2.2 Model the A c t i v i t y To f a c i l i t a t e c onceptual a c t i v i t y p l a n n i n g , the g e n e r a l p l a n n i n g model r e q u i r e s an i l l u s t r a t i v e method t h a t a l l o w s v i s u a l i z a t i o n of the f o l l o w i n g : l o g i c a l dependencies, f e a s i b l e d u r a t i o n s , and f e a s i b l e p r o d u c t i o n r a t e s f o r each o p e r a t i o n . A c t i v i t y Network A network model i s used t o r e p r e s e n t the l i n k s between o p e r a t i o n s and r e p e t i t i o n s of the a c t i v i t y . F i g u r e 16 shows an example l o g i c network. Only the l o g i c i s shown as d u r a t i o n s w i l l be a p p l i e d l a t e r . Crew o p e r a t i o n s are i d e n t i f i e d a t t h i s time. - 79 -^ACTIVITY LEVEL^ OPERATION LEVEL > PRECAST (option not shown) BEAMS/ I CAST IN PLACE TEMPORARY SHORE FOUNDATIONS SHORING TEMPORARY PILES tTEMPORARY  SPREAD FOOTINGS < STEEL < TIMBER CONCRETE TIMBER SYSTEM HEAVY TOWERS AND BEAMS vMANY LIGHT TOWERS / SCAFFOLDS PREFAB LENGTH OF ASSEMBLY FREE FORMING REBAR POST-BEND ON SITE PREBEND  PREFAB TENDONS ASSEMBLE IN SITU PREASSEMBLE  /PULL WITH WINCH TENSIONING^ .ASSEMBLE ON SITE/\PULL WITH TOW TRUCK C O N C R E T E < NORMAL STRENGTH HIGH EARLY STRENGTH PUMP CRANE AND BUCKET CURING TEMPERATURE CONTROL MOISTURE CONTROL. HEAT AND INSULATE ''BURLAP AND POLY SPRINKLER W WATER FORM REMOVAL LOWER FORMS WITH A CRANE DISASSEMBLE LOWER FORMS WITH JACKS Figure 15 Example Decision Tree for Activity Design TEMPORARY SHORE\~-FOUNDATION SHORING :  FORM PREASSEMBLY FORM PLACEMENT^ REBAR POST-TENSION DUCTING CONCRETE PLACEMENT AND CORING P. TENSION STRESSING FORM AND SHORE REMOVAL (STRIPPING) 3. CONSTRUCT 50 BEAMS. BEAM CYCLE IS REPETITIOUS. BEAM BEAM BEAM BEAM 5 6 7 8 \ BEAM BEAM 6 7 IDENTIFY CREWS > TEMPORARY SHORE FOUNDATION CREW SHORING AND FORMING CREW -« REBAR CREW ^ — P. TENSION CREW CONCRETE PLACEMENT CREW P. TENSION CREW FORM AND SHORE REMOVAL CREW F i g u r e 16 A c t i v i t y Precedence Network f o r the A c t i v i t y "Beam C o n s t r u c t i o n " - 81 -Ba r c h a r t f o r t h e U n i t A c t i v i t y C y c l e A " u n i t a c t i v i t y " i s d e f i n e d as one r e p e t i t i o n of an a c t i v i t y . For example, one span of the a c t i v i t y " c o n s t r u c t b r i d g e beams" i s a u n i t a c t i v i t y . A schematic b a r c h a r t i s now c o n s t r u c t e d f o r the u n i t a c t i v i t y . F e a s i b l e o p e r a t i o n d u r a t i o n s from p r e v i o u s job rec o r d s are i n c l u d e d t o a i d i n the conc e p t u a l d e s i g n of the a c t i v i t y . An example p r e l i m i n a r y b a r c h a r t f o r the u n i t a c t i v i t y o f beam c o n s t r u c t i o n i s shown i n f i g u r e 17. SHORE + FORM REBAR CREW OPERA-TIONS Crew C y c l e D u r a t i o n P/T C0NC/CURE STRESS One U n i t A c t i v i t y . One Beam C y c l e . STRIP TIME (Days) F i g u r e 17 : Barc h a r t f o r a U n i t A c t i v i t y of Beam C o n s t r u c t i o n - 8 2 -Time-Space Diagram A t i m e - s p a c e d i a g r a m c a n b e c o n s t r u c t e d f o r t h e u n i t a c t i v i t y t o s h o w r a t e s o f p r o d u c t i o n o f t h e v a r i o u s c r e w o p e r a t i o n s . T h i s t h e s i s u s e s t h e t e r m " c r e w o p e r a t i o n " i n t e r c h a n g e a b l y w i t h t h e t e r m " o p e r a t i o n " . I n t h e e x a m p l e g i v e n b e l o w , t h e t i m e - s p a c e d i a g r a m r e p r e s e n t s o p e r a t i o n s o f a n a c t i v i t y b e g i n n i n g a t l o c a t i o n 1 a n d p r o g r e s s i n g a t a c o n s t a n t r a t e . E a c h o p e r a t i o n s t a r t s o n e d a y a f t e r i t s p r e d e c e s s o r . L o c a t i o n o r R e p e t i t i o n 1 2 3 4 5 6 7 8 9 D a y s F i g u r e 1 8 E x a m p l e T i m e - S p a c e D i a g r a m 4 . 2 . 3 C r e w O p e r a t i o n S c h e d u l e T o B e L i n e a r a n d C o n t i n u o u s ? C r e w p r o g r e s s i s s a i d t o b e l i n e a r w h e n t h e s l o p e o f t h e t i m e -s p a c e d i a g r a m i s c o n s t a n t . C r e w p r o g r e s s i s s a i d t o b e c o n t i n u o u s b e c a u s e n o p a u s e a p p e a r s b e t w e e n w o r k l o c a t i o n s f o r e a c h o p e r a t i o n . U s u a l l y a w o r k c o n t i n u i t y c o n s t r a i n t s u g g e s t s t h a t w o r k o n a n o p e r a t i o n m u s t p r o c e e d c o n t i n u o u s l y . - 83 -L i n e a r p l a n n i n g can be u s e f u l f o r the f o l l o w i n g reasons: 1. L e a r n i n g curve e f f e c t s are maximized by d e d i c a t i n g each crew t o one t a s k and thus p r o d u c t i v i t y i s i n c r e a s e d . 2. Crew c y c l e d u r a t i o n s must be s t a n d a r d i z e d f o r e f f i c i e n t implementation of l i n e a r s c h e d u l i n g . I f the standard crew c y c l e d u r a t i o n i s a t t a i n e d , a b e n e f i c i a l rhythm of c o n s t r u c t i o n i s e s t a b l i s h e d which may a l s o i n c r e a s e p r o d u c t i v i t y . An i n c r e a s e i n p r o d u c t i v i t y w h i l e m a i n t a i n i n g a standard c y c l e d u r a t i o n i m p l i e s t h a t the crew s i z e decreases as the number of r e p e t i t i o n s i n c r e a s e s . In o r d e r f o r l i n e a r crew s c h e d u l i n g t o be f e a s i b l e , the a c t i v i t y i t s e l f must be c y c l i c a l , r e p e t i t i o u s , and have l i n e a r network l o g i c . I f the a c t i v i t y i s c o n s t r a i n e d by the number of forms a v a i l a b l e f o r placement, which most a c t i v i t i e s would be, then the o p e r a t i o n s are l i k e w i s e c o n s t r a i n e d . For e f f i c i e n t implementation of a l i n e a r schedule on such an a c t i v i t y , each o p e r a t i o n i d e a l l y would proceed a t the same r a t e as a l l the other o p e r a t i o n s . Each u n i t of o p e r a t i o n must be capable of being e f f i c i e n t l y completed i n the same amount of time as a l l other o p e r a t i o n s . T h i s d u r a t i o n i s c a l l e d the standard crew c y c l e d u r a t i o n . - 8 4 -4.2.4 Input L i n e a r C o n s t r a i n t s L i n e a r c o n s t r a i n t s , as p r e v i o u s l y mentioned, impose d u r a t i o n c o n s t r a i n t s . To develop l i n e a r s c h e d u l i n g f o r an a c t i v i t y , one i s f o r c e d t o s e l e c t a standard crew c y c l e d u r a t i o n f o r a l l o p e r a t i o n s b e f o r e c o n s i d e r i n g the methods u t i l i z e d by each crew o p e r a t i o n . The steps i n v o l v e d i n c l u d e 1) d e r i v i n g the crew c y c l e d u r a t i o n , 2) t e s t i n g f o r f e a s i b i l i t y , 3) t r e a t i n g non-c o n t i n u i t y , 4) computing u n i t a c t i v i t y c y c l e d u r a t i o n , and 5 computing falsework requirements where a p p r o p r i a t e . These steps are e l a b o r a t e d upon below. Step 1 D e r i v i n g the Crew C y c l e D u r a t i o n D e f i n i t i o n : "Concurrent crews" r e f e r s t o the number of crews employed on the same o p e r a t i o n a t the same time. 1 concurrent crew = Target A c t i v i t y P r o d u c t i o n Rate Standard Crew C y c l e Duration Beam A c t i v i t y Example: A c t i v i t y t a r g e t d u r a t i o n = 45 days Number of r e p e t i t i o n s = 10 Target a c t i v i t y p r o d u c t i o n r a t e = .222 beams per day - 85 -1 concurrent crew Standard Crew C y c l e D u r a t i o n 0.222 beams/day = 4.5 days / crew c y c l e The above e x p r e s s i o n i s i n e x a c t and u n c o n s e r v a t i v e because, while the f i r s t crew w i l l f i n i s h t h e i r p a r t of the a c t i v i t y c y c l e i n 4.5 days, the f i r s t a c t i v i t y c y c l e i s not complete u n t i l the l a s t crew i s f i n i s h e d . A b e t t e r e x p r e s s i o n f o r the standard crew c y c l e d u r a t i o n i s then: a c t i v i t y t a r g e t '-duration u n i t a c t i v i t y d u r a t i o n -1 # of concurrent 1— crews -1 s t a n d a r d crew c y c l e d u r a t i o n Number of A c t i v i t y U n i t s For the same example: 45 - 15 * 1 10 = 3 days crew c y c l e d u r a t i o n F i g u r e 19 g i v e s a g r a p h i c a l r e p r e s e n t a t i o n of t h i s e x p r e s s i o n . - 86 -L o c a t i o n s o r A c t i v i t y u n i t s 10 9 8 7 6 5 4 3 2 1 0 U n i t A c t i v i t y Duration < A c t i v i t y Target D u r a t i o n F i g u r e 19 Time-Space Diagram D e r i v i n g the Standard Crew C y c l e F i g u r e 19 shows g r a p h i c a l l y t h a t the p r o d u c t i o n r a t e f o r the crew-operation i n v o l v e d i n an a c t i v i t y has t o be g r e a t e r t h a t the a c t i v i t y p r o d u c t i o n r a t e (4.1.5) because of the crews t h a t have t o s t a r t a f t e r the a c t i v i t y s t a r t date. Crew-operation p r o d u c t i o n r a t e = Standard crew c y c l e d u r a t i o n - 8 7 -S t e p 2 T e s t f o r F e a s i b i l i t y o f S t a n d a r d C r e w C y c l e D u r a t i o n O n e m u s t n o w c h e c k p r e v i o u s r e c o r d s t o s e e i f t h e c a l c u l a t e d c r e w c y c l e d u r a t i o n i s a t t a i n a b l e f o r a l l c r e w o p e r a t i o n s . I f t h e c a l c u l a t e d s t a n d a r d c r e w c y c l e d u r a t i o n i s l e s s t h a n t h e d u r a t i o n t h a t t h e p r o d u c t i v i t y r e c o r d s i n d i c a t e i s f e a s i b l e , t h e f o l l o w i n g o p t i o n s a r e a v a i l a b l e : 1. A d d a n a d d i t i o n a l s h i f t f o r t h o s e o p e r a t i o n s t h a t r e q u i r e a d d i t i o n a l m a n h o u r s . 2 . F i n d m e t h o d s t h a t r e q u i r e l e s s t i m e f o r c o n s t r u c t i o n . 3 . M u l t i p l y t h e f o r m w o r k s y s t e m , m a n p o w e r a n d e q u i p m e n t r e s o u r c e s ( i . e . : i n c r e a s e t h e # o f c o n c u r r e n t c r e w s ) I f t h e c a l c u l a t e d v a l u e f o r t h e c r e w c y c l e d u r a t i o n i s l a r g e r t h a n o p t i m a l f o r t h e m a j o r i t y o f t h e o p e r a t i o n s , a n d o n l y o n e c o n c u r r e n t c r e w h a s b e e n u s e d , t h e c h o i c e s a r e a s f o l l o w s : 1. U s e t h e c a l c u l a t e d c r e w c y c l e d u r a t i o n w i t h s m a l l e r c r e w s . 2 . R e d u c e t h e a c t i v i t y t a r g e t d u r a t i o n t h u s r e d u c i n g t h e c r e w c y c l e d u r a t i o n . 3 . O p t f o r n o n l i n e a r s c h e d u l i n g . B u y f e w e r f o r m s . S c h e d u l e o t h e r w o r k t a s k s f o r t h e u n a s s i g n e d c r e w t i m e . - 8 8 -Step 3 A l l o w a b l e D e v i a t i o n from Standard Crew C y c l e D u r a t i o n I f one or more crews have c y c l e d u r a t i o n s l e s s than the standard crew c y c l e d u r a t i o n , then t h i s crew w i l l have a d i s c o n t i n u i t y of schedule and w i l l r e q u i r e a f i l l e r t a s k f o r the o f f days. A crew may not have a c y c l e d u r a t i o n g r e a t e r than the standard because a l l o f the other crews would have t o wait f o r t h i s crew. Some change i n method or res o u r c e s would be r e q u i r e d f o r t h i s long d u r a t i o n o p e r a t i o n i n order t o a d j u s t i t t o the standa r d c y c l e d u r a t i o n . Step 4 Determine U n i t A c t i v i t y C y c l e D u r a t i o n With the standard crew c y c l e d u r a t i o n s e l e c t e d , and wi t h crew o p e r a t i o n s overlapped where f e a s i b l e , a d u r a t i o n f o r the a c t i v i t y c y c l e can be determined. A b a r c h a r t w i t h o v e r l a p p i n g i s the source of u n i t a c t i v i t y c y c l e d u r a t i o n d e t e r m i n a t i o n . I t i s important t o r e a l i z e t h a t the amount of o v e r l a p p i n g w i l l i n f l u e n c e the number of falsework u n i t s r e q u i r e d f o r the case of l i n e a r a c t i v i t y s c h e d u l i n g . Step 5 Determine the N u m b e r o f Falsework U n i t s Required Since the number of falsework u n i t s o f t e n has l a r g e c o s t s a s s o c i a t e d with i t , the number of u n i t s r e q u i r e d needs to be c a l c u l a t e d a t t h i s p o i n t t o g a i n a proper f e e l f o r the e f f e c t s of the a c t i v i t y c y c l e and the crew c y c l e s on the number of falsework u n i t s r e q u i r e d . - 89 -Case 1; No o v e r l a p p i n g o f o p e r a t i o n s occurs on t h e u n i t a c t i v i t y  b a r c h a r t . s t a n d a r d crew c y c l e d u r a t i o n s u t i l i z e d . U n i t A c t i v i t y C y c l e D u r a t i o n # of Falsework U n i t s = Standard Crew C y c l e D u r a t i o n Beam A c t i v i t y Example: # of Beam C y c l e D u r a t i o n 15 Days Spans of = = = 5 Spans Falsework Standard Crew C y c l e D u r a t i o n 3 Days/Span F i g u r e 20a shows an a c t i v i t y b a r c h a r t with no o v e r l a p p i n g between o p e r a t i o n s where the above formula f o r falsework requirement c a l c u l a t i o n i s a p p r o p r i a t e . L o c a t i o n 5 4 3 2 1 r. Standard Crew C y c l e D u r a t i o n CU<o I 12 U n i t A c t i v i t y Duration -11 18 21 24 27 Days <-F i g u r e 20a A c t i v i t y Target D u r a t i o n B a r c h a r t Showing No Overlapping of Operations,  Falsework Requirement C a l c u l a t i o n Example. - 90 -Locat 5 4 3 2 1 i o n CAS*> i i 19 1 2 3 4 5 6 12 - i f 18 21 U n i t A c t i v i t y D u r a t i o n A c t i v i t y Target Duration = 23 24 27 Days F i g u r e 20b Barc h a r t Showing Ov e r l a p p i n g of Op e r a t i o n s .  Falsework Reguirement C a l c u l a t i o n Example. Case 2: O v e r l a p p i n g o f o p e r a t i o n s on the u n i t a c t i v i t y b a r c h a r t F i g u r e 2 0b shows the same a c t i v i t y with o v e r l a p p i n g of o p e r a t i o n s a p p l i e d . The above e x p r e s s i o n f o r falsework requirement i s no l o n g e r v a l i d . I f we s u b s t i t u t e (Crew-operation P r o d u c t i o n Rate) f o r (1 / Crew C y c l e D u r a t i o n ) , we again have a c o r r e c t e x p r e s s i o n f o r falsework u n i t s . Falsework u n i t s = (Unit A c t i v i t y Duration)(Crew-oper. Prod. Rate) Falsework Spans = 15 days x 0.5 span per day =7.5 Spans Use 8 Spans Another method of c a l c u l a t i n g the falsework requirement without f i r s t knowing the crew-operation p r o d u c t i o n r a t e i s as f o l l o w s : FU (NUA - 1) x UAD ATD - UAD Where: FU = Falsework U n i t s NUA = Number of U n i t A c t i v i t i e s UAD = U n i t A c t i v i t y D u r a t i o n ATD = Target A c t i v i t y D u r a t i o n NUA - 1 ATD - UAD i s the slope of the crew-operation p r o d u c t i o n r a t e l i n e . The product of t h a t s l o p e and the u n i t a c t i v i t y d u r a t i o n g i v e s the number of u n i t a c t i v i t i e s s t a r t e d and a l s o the number of falsework u n i t s r e q u i r e d p r i o r t o the completion of the f i r s t u n i t a c t i v i t y . The c a l c u l a t i o n of falsework u n i t requirement i s an i t e r a t i v e process with the design of the a c t i v i t y c y c l e . Steps 1 through 5 w i l l l i k e l y need t o be repeated u n t i l the most c o s t e f f e c t i v e combination of a c t i v i t y and crew-operation c y c l e s , t o g e t h e r w i t h falsework procurement i s reached. The d e s i g n w i l l not be f i n a l i z e d u n t i l a f t e r the o p e r a t i o n s have been i n d i v i d u a l l y assessed i n s e c t i o n 4.3 and are judged t o be a b l e t o achieve the c y c l e d u r a t i o n s c a l c u l a t e d i n t h i s e x e r c i s e . 4.2.5 S o r t Operations Before e n t e r i n g the o p t i o n loop f o r each o p e r a t i o n t o f i n d a minimum c o s t o p t i o n , i t i s d e s i r e a b l e t o s o r t the o p e r a t i o n s i n t o independant and interdependant groups. The independant o p e r a t i o n s w i l l be t r e a t e d i n d i v i d u a l l y w h i l e the interdependant o p e r a t i o n s w i l l be combined and c o s t i n g developed f o r the combined o p e r a t i o n s . In t h i s way the falsework system, f o r example, i s t r e a t e d as one combined o p e r a t i o n and the d i f f e r e n t system o p t i o n s are eva l u a t e d f o r the minimum c o s t system. Operations are then p r i o r i z e d t o a r r i v e a t a sequence f o r method s e l e c t i o n . A n a l y s i s w i l l be performed f i r s t on those o p e r a t i o n s w i t h the g r e a t e s t expected c o s t impact. - 93 -4.3 Operation Level 4.3.0 Introduction to Operation Level Design Parameters U n t i l now the General Planning Model has directed the process through l e v e l s of project overview, and a c t i v i t y organization and scheduling where the elements involved are known. The project i s given. The a c t i v i t i e s of the project are shown on the drawings. The constraints a f f e c t i n g each a c t i v i t y are discernable through the drawings. The project and a c t i v i t y l e v e l s have been largely concerned with organizing and sequencing the work to be done. The operation l e v e l i s where the design of the methods, materials, equipment, and sub-trades happens. 4.3.0.1 Decision Variables The design work required at the operation l e v e l concerns the followinq issues or variables: How?, How much?, How strong?, How many men?, How many crews?, What equipment?, What cost?, Exactly what material?, What sequence?, What methods? These questions require decisions to be made about several variables which constitute the design process. - 94 -The following l i s t of decision variables r e l a t e to manpower and schedule considerations. 1. hours per s h i f t 2. s h i f t s per day 3 . men per crew 4. supervision per crew Decision variables dealing with h o i s t i n g requirements include: 1. crane size 2. reach required 3 . mobile or tracked crane a. mobility required b. mobilization charges 4. duration and frequency of l i f t s Decision variables pertaining to the basic concrete construction operations of (i) Formwork, ( i i ) Rebar, and ( i i i ) Concrete placement are l i s t e d as follows. - 9 5 -( i ) Formwork 1 . f o r m m a t e r i a l : s t e e l , w o o d , o t h e r 2 . t e c h n o l o g y o f f o r m a s s e m b l y a . m a n u f a c t u r e r b . t y p e : o n e s i d e d , t w o s i d e d , t i e d , c . s i z e o f 1 s t c o m p o n e n t ( e g . p l y w o o d f o r m ) d . s i z e o f 2 n d c o m p o n e n t ( e g . w a l e m a t e r i a l ) e . f a s t e n e r s u s e d : b o l t s , w e l d s , n a i l s , w e d g e s f . m e a n s o f a s s e m b l y g . m e a n s o f s t r i p p i n g 3 . r e n t a l , p u r c h a s e , o r c o m p a n y o w n e d ? 4 . g e o m e t r i c d e s i g n o f t h e f o r m s y s t e m 5 . n u m b e r o f r e u s e s o f f o r m s 6. t r a n s p o r t m e t h o d b e t w e e n l o c a t i o n s a . c r a n i n g r e q u i r e d ? b . s l i d i n g o r w h e e l e d f o r m s ? c . h a n d c a r r i e d ? 7 . t o w e r s r e q u i r e d ? 8 . l a b o r t r a d e t o u t i l i z e S i n c e t h e r e a r e m a n y s u b - o p e r a t i o n s i n v o l v e d i n f o r m w o r k ( s h o r e f o o t i n g s , t o w e r s , p r e f a b , e r e c t , f r e e f o r m , a n d s t r i p ) , a s p r e a d s h e e t o f s u b - o p e r a t i o n s v e r s u s d e c i s i o n v a r i a b l e s w o u l d p r o v i d e a c o n c i s e f o r m a t f o r t h i s i n f o r m a t i o n . F i g u r e 2 1 s h o w s s u c h a s p r e a d s h e e t . - 96 -DECISION SUB-OPER Fccfcings iTIONS Tower Prefab Erect Freeform Strip VARIABLES Manpower Hrs/shift 8 8 10 10 8 Shifts/day 1 1 1 2 1 Men/crew 5 6 12 12 6 Foreman/cxew 1 1 1 1 1 Crane Crane size req no 50T 10T 50T 10T 50T Reach req no 25 20 25 25 25 Mobile/tracked Freq of l i f t s no 1/hr continu 3/day 2/day 5/day L i f t duration no lhr cont lhr l/4hr l/2hr Material Material type cone. Efco steel steel plywood steel Material quant 4yds/ftg 4/bay 20 5/bay 20shts/ba} f na Reuses 1 500 na 30 1 na Technolooy Manufacturer Stoneway Efco Efco Efco na na Type 3000psi heavy welded plates carpentry lower Size 1st camp. 12"x4'x4 20'hi Size 2nd camp. Fasteners req no boltec I welded bolted nailed bolted How assembled Procurement purchase owned rent rent purchase na Transport crane Y Y Y Y Sliding Wheeled Hand carried Y Trade labors Bridgemen Br Br Carps Labors Figure 21 Sub-operations Versus Decision Variables  For Operation = Formwork - 97 -( i i ) Reinforcing s t e e l variables Reinforcing s t e e l supply and assembly i s often subcontracted out but the following functions s t i l l need attention by the general contractor. 1. subcontract or in-house manpower? 2. d e t a i l i n g c r i t e r i a . a. construction j o i n t location: d i r e c t i o n required from the general contractor when j o i n t s have not been located by the design engineer. b. rebar assembly d e t a i l s . 3 . rebar placer same firm as supplier or d e t a i l e r ? 4 . laydown area available or o f f - l o a d at exact location? 5 . prebending or preassembly of rebar? 6. material handling: getting the s t e e l to the point of placing. 7. quantities of s t e e l to batch to s i t e at a time. 8 . coordination of rebar d e l i v e r i e s i n a timely manner. 9. hoisting requirements as above. 10. j i g s to hold rebar u n t i l t i e d . ( i i i ) Concrete placement variables These variables include: 1. mix design: strength, aggregate size, cement and water content - 98 -2 . a d d m i x t u r e s a . s u p e r p l a s t i c i z e r b . r e t a r d e r s 3 . p l a c i n g m e t h o d a . c r a n e a n d b u c k e t b . pump c . t a i l g a t e f r o m t r u c k 4 . w e a t h e r c o n t i n g e n c i e s 5 . d e l i v e r y r a t e f r o m p l a n t 6 . t r u c k a c c e s s t o s i t e 7 . p o u r r a t e 8 . v i b r a t i o n o r c o n s o l i d a t i o n t e c h n i q u e 9 . f i n i s h i n g m e t h o d s 1 0 . c u r e t i m e 1 1 . c u r e m e t h o d a . w a t e r c o n t a i n m e n t b . h e a t r e q u i r e m e n t s T h e a b o v e d e c i s i o n v a r i a b l e s a r e t h e i n g r e d i e n t s o f o p e r a t i o n m e t h o d s d e s i g n . G i v e n t h e c o n s t r a i n t s a n d p a r t i c u l a r s o f t h e j o b , ( o w n e r , s i t e , w o r k f o r c e , w e a t h e r , c l i m a t e , p l a n s a n d s p e c i f i c a t i o n s ) t h e r a t i o n a l c o m b i n a t i o n o f t h e a b o v e d e c i s i o n v a r i a b l e s c o n s t i t u t e s t h e o p e r a t i o n m e t h o d p l a n . - 99 -T h e o v e r r i d i n g c r i t e r i a f o r m e t h o d p l a n c o n s t r u c t i o n i s s i m p l e i n c o n c e p t a n d u n i v e r s a l t h r o u g h o u t t h e c o n s t r u c t i o n i n d u s t r y : 1. m i n i m i z e c o s t , 2. m i n i m i z e t h e t i m e d u r a t i o n , 3 . a n d m a x i m i z e q u a l i t y . T h e a b o v e d e c i s i o n v a r i a b l e s e a c h h a v e c o m p o n e n t s o f t i m e , c o s t , a n d q u a l i t y a s s o c i a t e d w i t h t h e m . T h e d i f f i c u l t y o r t h e c h a l l e n g e l i e s i n b e i n g a b l e t o i d e n t i f y w h a t c o s t s , t i m e d u r a t i o n s a n d q u a l i t y o f p r o d u c t a r e d i r e c t l y a p p l i c a b l e t o a n i n d i v i d u a l d e c i s i o n v a r i a b l e . B u t r e g a r d l e s s o f w h e t h e r t h e c o r r e c t c o s t o r d u r a t i o n o f a c h o i c e b e t w e e n t w o d e c i s i o n v a r i a b l e s ( m e t h o d s ) i s k n o w n , t h e d e c i s i o n h a s t o b e m a d e . H o w c a n t h e c o s t s a n d d u r a t i o n c o n s e q u e n c e s o f t h e d e c i s i o n v a r i a b l e s b e s t b e m e a s u r e d o r c a l c u l a t e d ? T h i s q u e s t i o n i s s o m e w h a t a d d r e s s e d i n t h e m o n i t o r i n g a n d c o n t r o l c h a p t e r o f t h i s t h e s i s , b u t o n a m o r e g l o b a l s c a l e . T h e m i s s i n g p o r t i o n i s a n y a t t e m p t t o s e p a r a t e o u t t h e e f f e c t s o f e a c h i n d i v i d u a l d e c i s i o n v a r i a b l e . T h i s i s a r e a l p r o b l e m i n t h e c o n s t r u c t i o n i n d u s t r y . B e c a u s e o f t h e l a r g e n u m b e r o f d e c i s i o n v a r i a b l e s , t h e i n t e r a c t i o n b e t w e e n v a r i a b l e s a n d l a c k o f a n a n a l y t i c a l f r a m e w o r k i n w h i c h t o l i n k t h e s e v a r i a b l e s , p r e d i c t i o n s o f c o s t a n d t i m e p e r f o r m a n c e i s a c o m p l e x t a s k . R e g r e s s i o n a n a l y s i s i s a p r o c e d u r e t h a t m i g h t y i e l d r e s u l t s g i v e n a d e t a i l e d , w e l l d o c u m e n t e d , c o n s t r u c t i o n d a t a b a s e - a n u n l i k e l y o c c u r a n c e . - 100 -T h i s r e s e a r c h o u t l i n e s the framework r e q u i r e d f o r c o n s t r u c t i o n of a d e t a i l e d database and a method of comparing and c o n t r a s t i n g the data. S e c t i o n s 5.2 and 5.3 and e s p e c i a l l y f i g u r e s 26, 27, and 28 show more d e t a i l concerning d a t a f i l e d e s i g n and data m a n i p u l a t i o n s a v a i l a b l e t o the system user. These data systems w i l l a f f o r d the user the a b i l i t y t o u t i l i z e more a n a l y t i c a l methods f o r d e c i s i o n v a r i a b l e q u a n t i f i c a t i o n . The implementation of the data c o l l e c t i o n framework and a method of q u a n t i f y i n g the t i m e - c o s t c h a r a c t e r i s t i c s of d e c i s i o n v a r i a b l e s i s l e f t t o f u t u r e r e s e a r c h . To a i d the a c t i v i t y d e s ign process i n the s h o r t term, the a c t i v i t y p l a n n i n g model p r o v i d e s f o r c h e c k l i s t s t o q u i c k l y i n s u r e t h a t a l l of the standard v a r i a b l e s have been c o n s i d e r e d . These c h e c k l i s t s can be e a s i l y made a p a r t of the i n f o r m a t i o n system and d i s p l a y e d f o r the o p e r a t i o n under c o n s i d e r a t i o n . 4.3.0.2 Required Output From Op e r a t i o n P l a n n i n g We now look a t the output r e q u i r e d from the p l a n n i n g process. The shop drawing i s the c o n v e n t i o n a l v e h i c l e f o r conveying i n f o r m a t i o n t o the owner, the g e n e r a l c o n t r a c t o r , and the foremen and crews i n the f i e l d . The f o l l o w i n g i n f o r m a t i o n i s u s u a l l y i n c l u d e d on the shop drawings f o r the r e f e r e n c e d o p e r a t i o n : - 1 0 1 -1 . e x c a v a t i o n : e x c a v a t i o n s e q u e n c e d r a w i n g f o r t u n n e l s t r u c t u r e s , s h o r i n g o f t h e e x c a v a t i o n w h e r e r e q u i r e d . 2. s h o r i n g : f o r m w o r k d e t a i l s , b i l l o f m a t e r i a l s , m a x i m u m c o n c r e t e p l a c i n g r a t e s , s t r i p p i n g p r o c e d u r e s . 3 . r e b a r : r e b a r d r a w i n g s , b a r l i s t s , s p l i c e l o c a t i o n s . 4 . c o n c r e t e : m i x d e s i g n , c o n s t r u c t i o n j o i n t s , l i f t d r a w i n g s . 5. p o s t - t e n s i o n i n g : t e n d o n a n d d u c t l a y o u t , s t r e s s i n g f o r c e a n d e l o n g a t i o n c a l c u l a t i o n s . F r o m t h e v i e w p o i n t o f t h e g e n e r a l c o n t r a c t o r , r e b a r a n d p o s t -t e n s i o n i n g a r e o f t e n s u b - c o n t r a c t e d o u t , a n d w i t h i t t h e r e s p o n s i b i l i t y f o r s u p p l y i n g s u c h i n f o r m a t i o n . I t i s o f t e n i n t h e g e n e r a l c o n t r a c t o r ' s i n t e r e s t t o h a v e i n p u t t o t h e s e d r a w i n g s s o t h a t h i s f o r m i n g d e t a i l s a r e n o t a d v e r s e l y a f f e c t e d b y r e b a r o r p o s t - t e n s i o n t e n d o n p l a c e m e n t . W i t h a l u m p s u m s u b - c o n t r a c t a r r a n g e m e n t , t h e g e n e r a l c o n t r a c t o r l o s e s c o n t r o l o v e r t h e m e a n s a n d m e t h o d s w i t h w h i c h t h e w o r k w i l l b e a c c o m p l i s h e d u n l e s s s u c h c r i t e r i a a r e i n c l u d e d a s a p a r t o f t h e s u b - c o n t r a c t d o c u m e n t s . W i t h a t i m e a n d m a t e r i a l s u b - c o n t r a c t , c o n t r o l o v e r m e a n s a n d m e t h o d s i s r e t a i n e d b y t h e g e n e r a l . T h e r e f o r e t h e d e c i s i o n t o s u b - c o n t r a c t t h e w o r k a n d t h e t y p e o f c o n t r a c t u t i l i z e d w o u l d i n s o m e c i r c u m s t a n c e s b e a p a r t o f t h e a c t i v i t y d e s i g n . F r o m t h e o u t p u t l i s t e d a b o v e , o n e c a n s e e t h a t d r a f t i n g a n d d r a w i n g p r o d u c t i o n a r e a n i n t e g r a l p a r t o f t h e d e s i g n p r o c e s s . D e p e n d i n g o n t h e a m o u n t o f s t a n d a r d i z a t i o n b e t w e e n d r a w i n g s , a c o m p u t e r a i d e d d e s i g n ( C A D ) s y s t e m m a y b e c o n s i d e r e d f o r t h e p u r p o s e o f a i d i n g t h e i n f o r m a t i o n o u t p u t s y s t e m . A n o t h e r v i e w o f - 1 0 2 -t h e p r o c e s s w o u l d h a v e t h e CAD s y s t e m a s a n i n t e g r a l p a r t o f t h e i n f o r m a t i o n s y s t e m . I n t h i s s i t u a t i o n t h e s y s t e m w o u l d s t o r e d r a w i n g s o f p a r t s , c o m p o n e n t s , o p e r a t i o n s , o r a c t i v i t i e s t h u s r e d u c i n g t h e w o r k r e q u i r e d t o r e c r e a t e i t f o r a n o t h e r l o c a t i o n o r f o r a f u t u r e p r o j e c t . F o r c e r t a i n a p p l i c a t i o n s , o n e c o u l d e n v i s i o n a n i n f o r m a t i o n s y s t e m t h a t w o u l d h a v e t h e CAD s y s t e m i n t e r f a c e d w i t h a d a t a b a s e s y s t e m s o t h a t a s c o m p o n e n t s a r e a s s e m b l e d o n t h e s h o p d r a w i n g , t h e c o s t s o f t h e i t e m s a r e l i s t e d t o a f i l e , a n i n v e n t o r y i s k e p t , a n d u s e f u l i n f o r m a t i o n c o n c e r n i n g p r o d u c t i o n r a t e s , p r o d u c t i v i t i e s a n d d u r a t i o n s a r e i n s t a n t l y a v a i l a b l e o n s c r e e n . L a t e r , d u r i n g t h e c o n s t r u c t i o n p r o c e s s , t h e same s y s t e m c o u l d be u s e d t o t r a c k t h e p r o c u r e m e n t o f t h e c o m p o n e n t s . CAD s y s t e m s a r e m o s t b e n e f i c i a l when d u p l i c a t i o n o f d r a w i n g s , a n d a l t e r a t i o n s o f t h e d u p l i c a t i o n s , a r e r e q u i r e d . When a r c h i t e c t s a n d e n g i n e e r s b e g i n u s i n g CAD s y s t e m s , (and some a r e ) a n d make t h e i r d r a w i n g s a v a i l a b l e t o t h e c o n t r a c t o r v i a e l e c t r o n i c d i s k s t o r a g e , t h e n t h e c o n t r a c t o r a n d s h o p d r a w i n g p r o c e s s w i l l r e a l l y b e n e f i t f r o m t h e u s e o f C A D . 4 . 3 . 1 C r e a t e O p e r a t i o n W o r k s h e e t I n w h a t f o l l o w s , a s c e n a r i o d e s c r i b i n g t h e u s e o f a c o m p u t e r b a s e d a c t i v i t y d e s i g n s y s t e m i s p r e s e n t e d . F rom t h i s s c e n a r i o , - 103 -s e v e r a l o f the a t t r i b u t e s r e q u i r e d of such system can be deduced. To begin the a c t i v i t y d e s i g n p r o c ess, we c a l l up the o p e r a t i o n p l a n n i n g worksheet screen. I t has the f o l l o w i n g i n f o r m a t i o n areas a v a i l a b l e : 1. Address: P r o j e c t , A c t i v i t y , and Oper a t i o n t o i d e n t i f y the a c t i v i t y d e s ign area. 2. A c t i v i t y c o n s t r a i n t l i s t i n g . 3. A r c h i v e d l i s t i n g of i d e n t i c a l or s i m i l a r d a t a f i l e summaries ( P r o j e c t , A c t i v i t y , and O p e r a t i o n ) , i n c l u d i n g a p p l i c a b l e methods and d e c i s i o n v a r i a b l e s . A l l r e c o r d s of f e a s i b l e method o p t i o n s are c o p i e d t o the screen and examined f o r a p p l i c a b i l i t y a g a i n s t the a c t i v i t y c o n s t r a i n t l i s t i n g , and a v a i l a b i l i t y . A method o p t i o n (an a l t e r n a t i v e method of c o n s t r u c t i o n ) i s a combination of s p e c i f i c v a l u e s of a p p l i c a b l e d e c i s i o n v a r i a b l e s . The most p r o m i s i n g o p t i o n s would then be processed through the o p t i o n c o s t i n g loop. 4. The c o s t i n g loop i s the process of e n t e r i n g the number of u n i t s of the o p e r a t i o n f o r the work i n q u e s t i o n , c o n s u l t i n g the c h e c k l i s t o f d e c i s i o n v a r i a b l e s , s e l e c t i n g the lowest u n i t c o s t method f o r the d e c i s i o n v a r i a b l e i n q u e s t i o n and e n t e r i n g t h a t method on the o p t i o n worksheet. The c o s t and d u r a t i o n are entered a u t o m a t i c a l l y on the r e c o r d . - 104 -For r e l i a b l e output, the c o s t i n g loop r e q u i r e s the r e l a t i o n s h i p s between p r o d u c t i v i t y r a t e s and the a p p l i c a b l e d e c i s i o n v a r i a b l e s t o be known. In p r a c t i c e and i n the a c t i v i t y p l a n n i n g model proposed, what w i l l be known i s the p r o d u c t i v i t y r a t e s achieved p r e v i o u s l y u t i l i z i n g c e r t a i n methods, equipment, crew s i z e , and m a t e r i a l s f o r a job having c e r t a i n c o n s t r a i n t s . But the e f f e c t s of i n d i v i d u a l d e c i s i o n v a r i a b l e s are ind e t e r m i n a t e . To be u s e f u l , the c o n t r a c t o r then needs t o be a b l e t o t r a n s l a t e the p r e v i o u s p r o d u c t i v i t i e s i n t o a c c u r a t e p r e c d i c t i o n s of p r o d u c t i v i t y f o r the p r o j e c t a t hand. As mentioned i n s e c t i o n 4.3.0.1 D e c i s i o n V a r i a b l e s , t h i s p l a n n i n g model p r o v i d e s a framework f o r c o l l e c t i n g , o r g a n i z i n g , comparing artd c o n t r a s t i n g the data on d e c i s i o n v a r i a b l e s . The process of t r a n s l a t i n g the data t o a new p r o j e c t i s l e f t t o the system u s e r s . Chapter 5, System Design Issues, d i s c u s s e s these i s s u e s more thoroughly. 5. A l i b r a r y index of photos and v i d e o s t h a t show p r e v i o u s o p e r a t i o n s b eing c o n s t r u c t e d i s a v a i l a b l e . The p r o j e c t photo f i l e i s c o n s u l t e d f o r the cand i d a t e o p t i o n s . T h i s photographic r e c o r d may be on v i d e o c a s s e t t e t o permit continuous viewing i n r e a l or compressed time. Use of time l a p s e photography may a l s o be employed f o r r e c o r d keeping and p r o d u c t i v i t y a n a l y s i s . - 105 -6. The CAD drawing program i s a c t i v a t e d w i t h a k e y s t r o k e and drawings of the candidate method o p t i o n s can be c a l l e d up from memory or c r e a t e d on s c r e e n . A f i r s t t r i a l shop drawing can then be produced, c o s t c a l c u l a t e d , and o p t i o n s compared. 4.3.2 C a l c u l a t e Major Resource Requirements Major re s o u r c e requirements r e f e r t o major equipment, falsework u n i t s , or any s p e c i a l apparatus r e q u i r e d f o r a s p e c i f i c o p t i o n . The f o l l o w i n g d i s c u s s i o n a p p l i e s s p e c i f i c a l l y t o c a l c u l a t i o n of the number of falsework u n i t s r e q u i r e i n order t o i l l u s t r a t e the concepts i n v o l v e d . I f l i n e a r s c h e d u l i n g has been used, then a u n i t a c t i v i t y d u r a t i o n has been estimated i n s e c t i o n 4.2. I f one chooses not t o schedule the a c t i v i t y l i n e a r l y , then t i m e / d u r a t i o n c o n s t r a i n t s are not imposed. One has the f l e x i b i l i t y t o wait u n t i l the o p t i o n s f o r each o p e r a t i o n are c o n s i d e r e d b e f o r e e s t a b l i s h i n g the o p e r a t i o n d u r a t i o n . However, an estimate of the a c t i v i t y c y c l e d u r a t i o n i s r e q u i r e d t o c a l c u l a t e the falsework resource requirement. T h i s i s accomplished by s e l e c t i n g the average u n i t a c t i v i t y d u r a t i o n from the p a s t job r e c o r d of the o p t i o n being c o n s i d e r e d . Check the c o n s t r a i n t s and s i t e c o n d i t i o n s of the p r e v i o u s job and compare them t o the p r e s e n t job c o n d i t i o n s . Modify the p r e v i o u s u n i t a c t i v i t y d u r a t i o n so as t o be c o n s i s t e n t w i t h the p r e s e n t c o n d i t i o n s . The formula f o r d e r i v i n g the number - 106 -of u n i t s o f falsework r e q u i r e d i s be s t i l l u s t r a t e d w i t h a time-space diagram. Assumptions: 1. The slowest crew i n the a c t i v i t y i s a b l e t o a c h i eve the prod-u c t i o n r a t e shown. 2. Falsework i s r e q u i r e d f o r the t o t a l l e n g t h of the a c t i v i t y d u r a t i o n . F i g u r e 22 Time-space Diagram Showing Falsework Requirements The a c t i v i t y i s completed when the l a s t o p e r a t i o n (crew 5) has completed the f i r s t r e p e t i t i o n . Crew 1 has j u s t completed r e p e t i t i o n 5 a t t h a t time. So formwork f o r r e p e t i t i o n s 1 through 5 need t o be a v a i l a b l e t o keep a l l f i v e crews working c o n t i n u o u s l y . The formula f o r the number of falsework u n i t s r e q u i r e d i s s l o p e of the crew-operation p r o d u c t i o n l i n e times u n i t a c t i v i t y d u r a t i o n equals the number of falsework u n i t s r e q u i r e d . See s e c t i o n 4.2.4 step 5 f o r a c a l c u l a t i o n procedure f o r falsework requirements. l o c a t i o n o r r e p e t i t i o n 6 5 4 3 2 1 9 12 15 18 Days 1 u n i t a c t i v i t y d u r a t i o n - 107 -Beam A c t i v i t y Examples : Option 1 : wood forms, a c t i v i t y u n i t d u r a t i o n = 25 days, n o n l i n e a r s c h e d u l i n g . (25 days * 0.253 beams/day) = 6.3, say 7 span l e n g t h s Option 2 : s t e e l . f o r m s , a c t i v i t y u n i t d u r a t i o n = 15 days, n o n l i n e a r s c h e d u l i n g . (15 days * 0.253 beams/day) = 3.8, say 4 span l e n g t h s Option 3 : s t e e l forms, a c t i v i t y u n i t d u r a t i o n = 15 days, crew c y c l e d u r a t i o n = 3.0 days, l i n e a r s c h e d u l i n g . (15 days * l/3days) = 5 span l e n g t h s Check the f e a s i b i l i t y of u t i l i z i n g the c a l c u l a t e d number of falsework u n i t s c o n c u r r e n t l y due t o space and b u i l d a b i l i t y c o n s t r a i n t s . The number of u n i t s o f falsework r e q u i r e d f o r the co n s i d e r e d o p t i o n i s now known. Sin c e the c o s t of falsework systems i s o f t e n v e r y s i g n i f i c a n t i n terms of the t o t a l a c t i v i t y c o s t , a d d i t i o n a l i t e r a t i o n s through the c o s t i n g and a c t i v i t y d e sign loop are l i k e l y t o be c o s t e f f e c t i v e . - 108 -4.3.3 Design Parameters Is d e s i g n i n p u t r e q u i r e d f o r an o p e r a t i o n ? I f "yes", con t i n u e . I f "no", go t o 4.3.4. I d e n t i f y the members t o be s i z e d and the m a t e r i a l s p r e s e n t l y i n the company i n v e n t o r y . I d e n t i f y r e n t a l m a t e r i a l s , i f a v a i l a b l e , and r a t e s t r u c t u r e . From h i s t o r i c a l r e c o r d s , i d e n t i f y p r e v i o u s l y u t i l i z e d assemblies and the components r e q u i r e d f o r t h e i r make-up. Beginning w i t h m a t e r i a l s owned by the company, d e v i s e a des i g n t h a t meets the requirements of the o p e r a t i o n i n q u e s t i o n . Consider the f o l l o w i n g shore and form example. As p r e v i o u s l y mentioned i n 4.3.0.2, the a c t i v i t y d e s i g n system would have the a b i l i t y t o s e l e c t an assembly, say a 200 k i p , 16 f o o t h i g h shore tower, from the CAD drawing r e c o r d s . With the a v a i l a b l e CAD f u n c t i o n s , the assembly can be p o s i t i o n e d and d u p l i c a t e d as r e q u i r e d . S i n c e the company owns t h i s tower, we assume t h a t the c o s t s of t r a n s p o r t a t i o n , assembly, e r e c t i o n , and s t r i p p i n g are w e l l known. Whether these c o s t s should be s t o r e d i n the i n t e g r a t e d drawing/cost database or i n the more c o n v e n t i o n a l p l a n n i n g a l g o r i t h m database i s not addressed here. Ren t a l equipment poses more v a r i a b l e s than w i t h company owned equipment as p r i c e s change, r e n t a l companies va r y from c i t y t o c i t y , and d i f f e r e n t equipment comes on l i n e . These r e n t a l items are e a s i l y c a t e g o r i z e d , dated, and s t o r e d w i t h the a s s o c i a t e d - 109 -s u p p l i e r i n f o r m a t i o n i n the database by the person who makes the i n q u i r y . The c h a l l e n g e i s t o keep i t c u r r e n t . The net r e s u l t of the above process i s a s k e t c h or shop drawing showing the work t o be b u i l t , the a s s o c i a t e d c o s t and d u r a t i o n , and the o p t i o n or r e v i s i o n number. 4.3.4 Cost C a l c u l a t i o n s With the q u a n t i t y t a k e - o f f i n u n i t s per span from 4.1.5, r a t e t a b l e s from 4.1.5, major resource requirements from 4.3.2, design i n p u t s from 4.3.3, and the job r e c o r d f o r the o p t i o n i n q u e s t i o n , c o s t c a l c u l a t i o n s f o r the method o p t i o n can now be made. 4.3.4.1 M a t e r i a l Cost C a l c u l a t i o n s L i s t the components of the o p e r a t i o n s and o p t i o n s b e i n g c o s t e d . A spread sheet format would be used t o compile the data and perform the c a l c u l a t i o n s . T h i s model proposes t o sum the m a t e r i a l c o s t s and d i v i d e by the number of a c t i v i t y u n i t s to get c o s t per u n i t a c t i v i t y , ( i . e . $/span). Regardless of which u n i t s are u t i l i z e d , the same u n i t s must be used f o r a l l items of the same type. - 110 -4.3.4.2 Labour Cost C a l c u l a t i o n s T h i s model assumes t h a t p r o d u c t i v i t y r e c o r d s are a v a i l a b l e f o r each o p e r a t i o n o p t i o n . I f t h i s i s not the case, then p r o d u c t i v i t y e s t i m a t e s or a f u r t h e r breakdown t o the work t a s k l e v e l w i l l be r e q u i r e d . P r o d u c t i v i t y would be a v a i l a b l e i n spans/manday and units/manday, both of which would be u s e f u l . ( U n i t s here r e f e r t o m, m2, m3, kg, etc.) The formula f o r labour c o s t i s : Labour Cost = (Avg. U n i t s / s p a n * Labour Rate) Span P r o d u c t i v i t y Formwork Example: $/Span = (Avg. m 2/span * $/manday) m2/manday 4.3.4.3 Equipment Cost C a l c u l a t i o n s Again we assume t h a t we have equipment p r o d u c t i v i t y r e c o r d s f o r the major o p e r a t i o n s and e s p e c i a l l y f o r o p t i o n s t h a t have been used i n p r e v i o u s j o b s . P r o d u c t i v i t y r e c o r d s would i n c l u d e type and s i z e of equipment, c o s t per hour, hours charged t o the o p e r a t i o n s i n q u e s t i o n s per span or per p i e r and hours per u n i t . The formula f o r equipment c o s t i s : Equipment Cost/span = (# of u n i t s / s p a n * $/hour) Equipment P r o d u c t i v i t y Concrete Pump Example: $/span = fm 3/span * $/hour) m 3/hour Falsework Crane Cost Example: $/span = towers/span + forms/span * $/hour tower/hour forms/hour 4.3.4.4 T o t a l Cost Per Option Having d e r i v e d m a t e r i a l , manpower and equipment c o s t s , i t i s a simple matter t o sum these r e s u l t s and get a t o t a l c o s t per span f o r the o p t i o n b e i n g c o n s i d e r e d . - 112 -4 . 3 . 5 L a s t : O p t i o n ? C h o o s e M i n i m u m C o s t O p t i o n T h e o p t i o n l o o p r e p e a t s i t s e l f u n t i l a l l t h e o p t i o n s h a v e b e e n a n a l y s e d a n d a t o t a l c o s t d e r i v e d . T h e w o r k s h e e t c o n t a i n i n g t h e c o s t o p t i o n a n a l y s i s , m a j o r a s s u m p t i o n s , a n d t h e p r e l i m i n a r y d r a w i n g s a r e n o w p r e s e n t e d t o t h e c o n s t r u c t i o n t e a m f o r c o n s i d e r a t i o n . O f t e n t i m e s , i d e a s f r o m t h e s e o t h e r p l a y e r s w i l l i n f l u e n c e t h e d e t a i l s a n d e v e n m a j o r a s p e c t s o f t h e d e s i g n . I t e r a t i o n s e e m s t o b e t h e n a t u r e o f g o o d a c t i v i t y d e s i g n . F i n a l l y , t h e m i n i m u m c o s t o p t i o n i s t e n t a t i v e l y s e l e c t e d a n d f i n a l d r a w i n g s p r e p a r e d f o r t h e o p e r a t i o n . 4 . 3 . 6 C a l c u l a t e C r e w S i z e a n d T e s t D u r a t i o n T h e c r e w s i z e r e q u i r e d i s a f u n c t i o n o f t h e e s t i m a t e o f p r o d u c t i v i t y o f t h e c r e w o p e r a t i o n a n d t h e t i m e a v a i l a b l e t o a c c o m p l i s h t h e o p e r a t i o n . T h e f o l l o w i n g m e t h o d s a r e u t i l i z e d t o c a l c u l a t e c r e w s i z e d e p e n d i n g o n w h e t h e r o r n o t t h e c r e w o p e r a t i o n s a r e l i n e a r a n d t h e c r e w c y c l e d u r a t i o n s a r e s p e c i f i e d . - 1 1 3 -4 . 3 . 6 . 1 C r e w C y c l e D u r a t i o n S p e c i f i e d , ( L i n e a r P l a n n i n g ) T h e a s s u m p t i o n h e r e i s t h a t u n i t p r o d u c t i v i t y i s i n d e p e n d e n t o f c r e w s i z e . A n d f o r a c e r t a i n r a n g e o f c r e w s i z e , t h i s a s s u m p t i o n w i l l g e n e r a l l y b e t r u e . H o w e v e r , t h e a s s u m p t i o n m u s t b e t e s t e d . C r e w S i z e = A v e r a g e # U n i t s / s p a n C r e w C y c l e D u r a t i o n # o f C o n c u r r e n t C r e w s P r o d u c t i v i t y F o r m w o r k E x a m p l e : C r e w S i z e = 2 5 0 m 2 / s p a n (3 d a y s / s p a n ) * ( 1 c r e w ) * ( 1 2 m 2 / m a n d a y ) m e n c r e w = 6 . 9 4 m e n / c r e w : u s e 7 m a n c r e w T e s t t h e c a l c u l a t e d c r e w s i z e a g a i n s t t h e p a s t r e c o r d c r e w s i z e o f t h e s e l e c t e d o p t i o n . I f t h e p r e s e n t c a l c u l a t e d c r e w s i z e i s s i g n i f i c a n t l y l a r g e r , t h e n t h e r e i s a g o o d c h a n c e t h a t t h e p r e s e n t p r o d u c t i v i t y w i l l b e l e s s t h a n t h a t o f t h e p r e v i o u s j o b a n d t h e c a l c u l a t e d c r e w s i z e w i l l b e i n s u f f i c i e n t . S h o u l d t h i s h a p p e n , o n e n e e d s t o c r i t i c a l l y e x a m i n e t h e a s s u m p t i o n s m a d e c o n c e r n i n g c r e w c y c l e d u r a t i o n a n d p r o d u c t i v i t y . S o l u t i o n s t o t h e p r o b l e m m a y i n v o l v e a d d i n g a n i g h t s h i f t o r c h a n g i n g c o n s t r u c t i o n m e t h o d s t o i n c r e a s e p r o d u c t i v i t y . A n o t h e r s o l u t i o n w o u l d i n v o l v e a n o t h e r p a s s t h r o u g h t h e o p t i o n l o o p - 1 1 4 -l o o k i n g f o r a f a s t e r m e t h o d o f c o n s t r u c t i o n a n d t r a d i n g m i n i m u m c o s t f o r a s h o r t e r d u r a t i o n . 4 . 3 . 6 . 2 C r e w C y c l e D u r a t i o n N o t S p e c i f i e d I n t h i s c a s e o n e w o u l d c h o o s e a c r e w s i z e t h a t i s k n o w n f r o m e x p e r i e n c e t o y i e l d n e a r o p t i m a l p r o d u c t i v i t y . T h e o p e r a t i o n d u r a t i o n i s t h e n c a l c u l a t e d . W i t h t h e o p t i o n s e l e c t e d , a n d t h e c o s t , c r e w s i z e , a n d d u r a t i o n e s t i m a t e d , t h e i n i t i a l d e s i g n o f t h e o p e r a t i o n i s c o m p l e t e . T h e e s s e n t i a l i n f o r m a t i o n a n d m a j o r a s s u m p t i o n s c a n t h e n b e a s s e m b l e d f o r r e v i e w p u r p o s e s . 4 . 3 . 7 L a s t O p e r a t i o n T h e o p e r a t i o n l o o p i s r e p e a t e d u n t i l a l l o p e r a t i o n s o f t h e a c t i v i t y a r e d e s i g n e d b a s e d o n o n e o f t h e f o l l o w i n g : 1 . l i n e a r s c h e d u l i n g : s e l e c t e d c r e w c y c l e d u r a t i o n , m i n i m u m c o s t g i v e n c r e w c y c l e d u r a t i o n , a n d f e a s i b l e c r e w s i z e . o r - 1 1 5 -2. n o n - l i n e a r s c h e d u l i n g : minimum c o s t , o p t i o n a l crew s i z e , and d u r a t i o n dependent on p r o d u c t i v i t y and crew s i z e . 4.4 A c t i v i t y L e v e l R e s u l t s At t h i s p o i n t the v a r i o u s o p e r a t i o n methods have been s e l e c t e d and the c o s t s are known. A c r i t i c a l i n s p e c t i o n o f the s e l e c t e d o p e r a t i o n s i s now performed. S i n c e a l l o p e r a t i o n s of an a c t i v i t y i n t e r a c t t o some degree, one must check t h a t t h e r e are no major c o n f l i c t s and t h a t the o p e r a t i o n s can be c o n s t r u c t e d as planned. In d e a l i n g w i t h c o n f l i c t s , one may have t o check the i n t e r a c t i o n between o p e r a t i o n s on an hour by hour b a s i s , p a r t i c u l a r l y f o r reso u r c e c o n f l i c t s such as crane useage. 4.4.1 Major Equipment Resource L e v e l l i n g Equipment hours have a l r e a d y been computed i n a p r e v i o u s step. By c a l c u l a t i n g the r e q u i r e d equipment hours f o r a l l o p e r a t i o n s of the a c t i v i t y , one can c o n s t r u c t a resource histogram. With the histogram developed, one can l e v e l the equipment resource by a l t e r i n g the schedule of the o p e r a t i o n s . Two p o i n t s need t o be addressed p r i o r t o l e v e l l i n g . - 116 -1. F l o a t i s r e q u i r e d t o perform l e v e l l i n g of r e s o u r c e s . Is f l o a t a v a i l a b l e i n the schedule of o p e r a t i o n s t o be l e v e l l e d ? 2. Which proceedure has the h i g h e r p r i o r i t y , crane resource l e v e l l i n g o r maintenamce of l i n e a r and or continuous s c h e d u l i n g f o r the o p e r a t i o n s o f an a c t i v i t y ? An example f o r the a c t i v i t y "BEAM CONSTRUCTION" has been developed and i s shown i n f i g u r e 23. In the example, the crane resource schedule compiles a c t i v i t y bar c h a r t s f o r beams 1 through "n". The b a r c h a r t f o r beam 1 can be i d e n t i f i e d by the heavy o u t l i n e . For each day and each o p e r a t i o n on the b a r c h a r t the number of expected hours o f crane use i s entered. The column a t the l e f t shows the s i z e of crane r e q u i r e d f o r each o p e r a t i o n of the beam a c t i v i t y . The crane requirements i n t h i s example can be adequately met with one 100 ton (large) crane and one 10 ton (small) crane. The summation of crane hours i s shown CRANE RESOURCE SCHEDULE CRANE HOURS PER DAY SHOWN FOR EACH OPERATION Schedule assumes 5 beams being constructed concurently as per a c t i v i t y bar chart. ACTIVITY START-UP PHASE SIZE OF CRANE REQUIRED, (TONS) 100 10 100 SHORE & FORM STRIPPING P.T. STRESSING (CONCRETE PUMPED IN THIS PLAN) CONCRETE/ CURE P.T. DUCTING REBAR SHORE a FOlfo | 0 FULL PRODUCTION SUMMATION OF CRANE HOURS I SMALL CRANE HRS. LARGE CRANE HRS. 5 5 TT 8 •"6" LEVEL CRANE HRS. SMALL CRANE LARGE CRANE Figure 23 Example Barchart and Resource L e v e l l i n g Diagram  Showing Crane Hours Per Operation - 118 -i n r o w s A a n d B . W h e n t h e s u m m a t i o n i s k n o w n f o r a t y p i c a l c y c l e d u r a t i o n ( s h o w n i n d o t t e d o u t l i n e ) , t h e r e s o u r c e c a n b e l e v e l l e d . A n e x a m p l e o f t h e l e v e l l e d c r a n e h o u r s i s s h o w n i n r o w s C a n d D . I n t h i s c a s e t h e l e v e l l i n g r e q u i r e d i s v e r y m o d e r a t e a n d c o u l d b e a c c o m p l i s h e d w i t h m i n o r c h a n g e s t o t h e o p e r a t i o n s c h e d u l e a n d , o r m e t h o d s . 4.4.2 R e f i n e m e n t o f A c t i v i t y S c h e d u l e T h e c r i t i c a l p a t h n e t w o r k , b a r c h a r t a n d t i m e - s p a c e d i a g r a m s h a v e a l l b e e n d e s c r i b e d i n s e c t i o n ( 4 . 2 . 2 ) . T h e r e f i n e m e n t p r o c e d u r e s p e r f o r m e d n o w a r e t h e s a m e a s d e s c r i b e d i n t h a t s e c t i o n e x c e p t t h a t n o w w e h a v e o p e r a t i o n m e t h o d s a n d d u r a t i o n e s t i m a t e s b a s e d o n d e t a i l e d a n a l y s i s a t t h e o p e r a t i o n l e v e l . T h e l o g i c b e t w e e n o p e r a t i o n s a n d t h e d u r a t i o n s c a n n o w b e i n p u t i n t o t h e s e s c h e d u l i n g m e t h o d s . T h e o u t p u t w i l l b e r e f i n e d u n i t a c t i v i t y d u r a t i o n s t h a t c a n b e c h e c k e d a g a i n s t t h e d u r a t i o n a s s u m p t i o n s p r e v i o u s l y m a d e . 4.4 . 3 P r e l i m i n a r y D e s i g n o f A c t i v i t y i i s C o m p l e t e T h e r e s u l t s w o u l d b e f i l e d t o c o m p u t e r d i s k a n d o r g a n i z e d f o r r e v i e w . I n c l u d e d w i l l b e a l l a s s u m p t i o n s a n d c o n s t r a i n t s p e r t a i n i n g t o t h e a c t i v i t y . P r e s e n t a t i o n o f t h e f i n a l d e s i g n o f t h e a c t i v i t y i s n o w m a d e t o t h e c o n s t r u c t i o n t e a m . - 119 -4.4.4 L a s t A c t i v i t y ? T h e a c t i v i t y d e s i g n p r o c e s s i s r e p e a t e d u n t i l a l l a c t i v i t i e s h a v e b e e n d e s i g n e d . 4 . 5 P r o j e c t R e s u l t s W i t h t h e a c t i v i t y m e t h o d s , e q u i p m e n t , c o s t s , a n d d u r a t i o n s c l o s e l y e s t i m a t e d , o n e m u s t e x a m i n e t h e r e s u l t s f r o m t h e p r o j e c t l e v e l t o e n s u r e t h e f o l l o w i n g c r i t e r i a a r e m e t : 1. T h e p r o j e c t p l a n i s l o g i c a l l y c o r r e c t . 2. T h e s c h e d u l e m e e t s t h e m i l e s t o n e r e q u i r e m e n t s ( a c t i v i t y c r a s h i n g m a y b e n e c e s s a r y i f t h e s c h e d u l e d d u r a t i o n e x c e e d s t h e c o n t r a c t d u r a t i o n ) . 3 . R e s o u r c e s a r e r e a s o n a b l y l e v e l l e d . 4 . E a r l y s t a r t v s . l a t e s t a r t s t r a t e g i e s a r e a d d r e s s e d f o r r i s k m a n a g e m e n t . 5 . A c t i v i t y a n d p r o j e c t a s s u m p t i o n s , m e t h o d s , c o s t s , m a t e r i a l s , e q u i p m e n t , a n d s c h e d u l e s a r e r e v i e w e d a n d a p p r o v e d b y t h e c o n s t r u c t i o n t e a m . T h e p l a n n i n q p h a s e o f t h e c o n s t r u c t i o n i n f o r m a t i o n s y s t e m e n d s h e r e . T h e m o d e l n o w e n t e r s t h e m o n i t o r i n g a n d c o n t r o l p h a s e a n d a d d r e s s e s d a t a c o l l e c t i o n a n d p r o j e c t c o n t r o l i s s u e s . - 120 -CHAPTER 5. SYSTEM DESIGN ISSUES 5.0 I n t r o d u c t i o n In t h i s c h apter we w i l l d i s c u s s d a t a f i l e s and i n f o r m a t i o n storage requirements f o r a comprehensive c o n s t r u c t i o n i n f o r m a t i o n system. The subset of i n f o r m a t i o n r e q u i r e d f o r the a c t i v i t y d e s i g n problem i s h i g h l i g h t e d . The dominant i s s u e s are as f o l l o w s : 1. Type of i n f o r m a t i o n r e q u i r e d and c a t e g o r i e s t o c o n t a i n i t (see s e c t i o n 5.1 f o r conceptual d a t a f i l e d e s i g n ) . 2. Type of software system t o use as the database ( f o r a database system see 5.2; f o r a m u l t i d i m e n s i o n a l spreadsheet system see 5.3.) 3. Number of t i e r s of h i e r a r c h y i n which t o s t o r e the i n f o r m a t i o n ( f o r a 5 t i e r system see 5.2; f o r an 8 t i e r system see 5.3.) 5.1 Conceptual D a t a f i l e Design The f o l l o w i n g f i l e c a t e g o r i e s , headings, and d e s c r i p t i o n s show the o r g a n i z a t i o n and type of i n f o r m a t i o n r e q u i r e d i n an i n t e g r a t e d c o n s t r u c t i o n i n f o r m a t i o n system. - 121 -Category Name D e s c r i p t i o n / Content D e f i n i t i o n f i l e s P r o j e c t A c t i v i t y O p e r a t i o n Information entered once. e.g. f u l l name, code number, d e s c r i p t i o n , c o n d i t i o n s , methods of c o n s t r u c t i o n , e t c . (see f i g u r e 25) Information f i l e s Employee Equipment Sub c o n t r a c t o r Vendor I d e n t i f i c a t i o n number, address, phone number, h o u r l y r a t e , c o n t r a c t u a l i n f o r m a t i o n , e t c . T r a n s a c t i o n f i l e s Timesheet Purchase order Accounting summary P a y r o l l Accounts payable One r e c o r d per t r a n s a c t i o n . T h i s i s the data source f o r most of the i n f o r m a t i o n system. (see f i g u r e 26) Summary f o r accounting purposes Data c o l l e c t i o n summary f i l e s Summary of t r a n s a c t i o n s c r o s s t a b u l a t e d by p r o j e c t , d i v i s i o n , a c t i v i t y , o p e r a t i o n , l o c a t i o n , r e s o u r c e , d e s c r i p t o r , phase, (see f i g u r e 27) Data t r a n s -formation f i l e s Take a r c h i v e d r e c o r d s and c r e a t e p r e s e n t d o l l a r v a l u e r e c o r d s from the p r e v i o u s c o s t s . F i l e s r e q u i r e d t o compare h i s t o r i c a l c o s t s with new p r o j e c t estimated c o s t s , (see f i g u r e 28) F i g u r e 24 D a t a f i l e Overview For an I n t e g r a t e d C o n s t r u c t i o n Information System - 1 2 2 -There are many f e a s i b l e methods of o r g a n i z i n g data f o r c o n s t r u c t i o n i n f o r m a t i o n systems. Two examples of f i l e d e s i g n are d i s c u s s e d h e r e i n . The f i r s t uses a database concept such as Dbase III+ and i d e n t i f i e s the f i e l d s r e q u i r e d f o r d a t a c o l l e c t i o n . The second uses the TM1 m u l t i d i m e n s i o n a l spreadsheet as a model and shows the data organized i n an e i g h t t i e r h i e r a r c h y . In both examples, the i n f o r m a t i o n s t o r e d i s i d e n t i c a l . The d i f f e r e n c e i s t h a t where the 5 t i e r h i e r a r c h y r e q u i r e s 40 p l u s columns of data, the 8 t i e r h i e r a r c h y r e q u i r e s o n l y e i g h t . The 8 t i e r h i e r a r c h y w i l l need more rows t o d i s p l a y a l l the data. The key i s how the chosen system w i l l be a b l e t o compare and c o n t r a s t the data items of i n t e r e s t . 5.2 D a t a f i l e Design: Dbase Format and 5 I d e n t i t y F i e l d s . F i g u r e s 25 through 28 p r e s e n t example f i l e s w i t h f i e l d s (column headings) r e q u i r e d f o r data storage i n a database format. The p r i n c i p l e of the r e l a t i o n a l database i s t h a t one i s a b l e t o u t i l i z e m u l t i p l e databases and t o r e l a t e data r e c o r d s v i a common elements i n the designated f i e l d . For i n s t a n c e , "from p r o j e c t f i l e s xCambie B r i d g e ' and xQueens Bridge', s e l e c t r e c o r d s where a c t i v i t y = beams and o p e r a t i o n = c o n c r e t e . " With t h i s statement, a l l records t h a t f u l f i l l the above requirements w i l l be d i s p l a y e d on the screen. - 123 -T h i s p r i n c i p l e i s u t i l i z e d f o r the o r g a n i z a t i o n of the a c t i v i t y data c o l l e c t i o n f i l e . The r e c o r d s or rows would have the f i r s t f i v e f i e l d s as unique or i d e n t i f y i n g f i e l d s . These correspond t o the h i e r a c h y of p r o j e c t , d i v i s i o n , a c t i v i t y , o p e r a t i o n , and l o c a t i o n . The t h r e e remaining dimensions, r e s o u r c e ( l a b o r , equipment, m a t e r i a l , s u b - c o n t r a c t o r ) , d e s c r i p t o r ( t i m e , c o s t , method), and phase(bid, estimate, f o r e c a s t , a c t u a l , a r c h i v e ) are shown wit h a l l of t h e i r elements d i s p l a y e d as f i e l d s . In the paragraphs t o f o l l o w , the f i l e c a t e g o r i e s necessary t o the i n f o r m a t i o n system are d i s c u s s e d . 5.2.1 D e f i n i t i o n f i l e s (see f i g u r e 25) These f i l e s are r e q u i r e d t o d e s c r i b e the g l o b a l (overview) parameters f o r p r o j e c t s , a c t i v i t i e s , and o p e r a t i o n s . They c o n t a i n i n f o r m a t i o n on c o n s t r a i n t s , g e n e r a l c o n d i t i o n s , c o n t r a c t type, owner, e t c . These f i l e s should have sentence and memo c a p a b i l i t i e s . They g e n e r a l l y do not c o l l e c t volumes of numerical data. - 124 -5.2.2 Timesheet F i l e (see f i g u r e 26) Data c o l l e c t i o n from the p r o j e c t c o n t r o l module i s one of the main sources of i n f o r m a t i o n f o r an i n f o r m a t i o n system. T h i s f i l e shows the t y p i c a l data r e q u i r e d from timesheets f o r an on-going c o n s t r u c t i o n p r o j e c t . The data i s t r a n s a c t i o n a l (one r e c o r d f o r one t r a n s a c t i o n ) . In t h i s case t h e r e i s one r e c o r d per timesheet f o r each employee or each p i e c e of equipment. N o t i c e t h a t i n the example timesheet f i l e , l a b o r , equipment, and s u b - c o n t r a c t o r time can be entered and coded w i t h i n the same f i l e . Project d e f i n i t i o n f i l e Project Project Tender Owner Project Estimate Engineer or Contract Code tt Name Date Name Location Type Archit e c t S eg eg Name 5 1 0 0 . lump sum A c t i v i t y d e f i n i t i o n f l l * Proj A c t i v i ty A c t i v i t y A c t i v i t y Conditions Time Physical Method Code Code « Name Descriptn Constraints Constraints nemo I •partition d e f i n i t i o n f i l a Proj Operation Operation Operation Conditions Comments Method Code Code Name Description Demo Figure B5 D e f i n i t i o n Film Structure! Deilu Tlmeeheet F i l e (Includes Labor, Equipment, and Sub-contractors) Date Proj D i v i s i o n A c t i v i t y Operation Location Name CodB Hrly Rate Time Time Time S s Code CodB Name Name Number (labor) Labor - L RatB i n c l Reg DT 0T Reg 0T x x x x X X X X X X (Equip) Equip - E Bf ts (1 .S) (2.0) (Subs) Sub - S Figure SE Dellu Tlmeeheet F i l e Structure - 1 2 6 -5 . 2 . 3 A c t i v i t y - O p e r a t i o n D a t a C o l l e c t i o n F i l e ( s e e f i g u r e 2 7 ) T h e a c t i v i t y - o p e r a t i o n d a t a c o l l e c t i o n f i l e a p p e a r s n e x t a n d c o n t a i n s a l l n e c e s s a r y d a t a f i e l d s f o r c o n t r o l l i n g a n a c t i v i t y o r a n o p e r a t i o n o f a c o n s t r u c t i o n p r o j e c t . I n f i g u r e 2 7 t h e f i e l d s a r e s o n u m e r o u s t h a t t h e y d o n o t f i t o n o n e l i n e a n d i n t h a t i n s t a n c e t h e f i e l d s a r e s h o w n w r a p p e d a n d o c c u p y i n g t w o l i n e s . T h e f o r t y p l u s f i e l d s w i t h i n t h e f i l e a r e o r g a n i z e d b y d e s c r i p t i o n a n d c o d e n u m b e r s , q u a n t i t y t a k e o f f , t i m e a n d d a t e , m a n p o w e r , e q u i p m e n t , m a t e r i a l , s u b - c o n t r a c t o r , t o t a l s , a n d m e t h o d o l o g y . T h e d a t a w o u l d b e a u t o m a t i c a l l y t r a n s m i t t e d f r o m t h e t i m e s h e e t f i l e u s i n g p r o j e c t , a c t i v i t y , o p e r a t i o n , a n d l o c a t i o n n a m e a n d n u m b e r s t o c o d e t h e d e s t i n a t i o n f i l e a n d r e c o r d . T h u s f o r e v e r y p r o j e c t c o d e , a c t i v i t y n a m e , a n d o p e r a t i o n n a m e , f o r w h i c h l a b o r , e q u i p m e n t , o r s u b - t r a d e s a r e c o d e d , t h e r e w o u l d e x i s t a f i l e a n d a f i e l d t o c o l l e c t d a t a . F o r e v e r y l o c a t i o n c o d e w h e r e t h e a c t i v i t y i s r e p e a t e d , t h e r e w o u l d b e a r e c o r d c o n t a i n i n g t h e c u m u l a t i v e a m o u n t s o f e a c h i t e m f o r e v e r y f i e l d . W h e n t h e a c t i v i t y - o p e r a t i o n i s c o m p l e t e d , t h e f i l e f o r t h a t a c t i v i t y - o p e r a t i o n w i l l c o n t a i n o n e r e c o r d f o r e v e r y l o c a t i o n . I n t h i s w a y d i r e c t c o m p a r i s o n o f p r o d u c t i o n v a l u e s b e t w e e n l o c a t i o n s i s p o s s i b l e . T h e l a s t r e c o r d s o f e a c h f i l e w i l l c o n t a i n s t a t i s t i c a l s u m m a r i e s o f t h e f i e l d v a l u e s f o r a l l l o c a t i o n s . C u m u l a t i v e , m e a n , a n d s t a n d a r d d e v i a t i o n v a l u e s w o u l d b e k e p t c u r r e n t . T h e s e s u m m a r y r e c o r d s a r e t h e n p o s t e d t o t h e a c t i v i t y d a t a c o l l e c t i o n s u m m a r y f i l e . I t s i s a m e t h o d o f c o n d e n s i n g t h e d a t a t o m e a n i n g f u l q u a n t i t i e s . A c t i v i t y - Q p a r a t t o n Data C o l l a o t l o n F i l a ( r e c o r d s c o n t a i n d a t a o f e a c h l o c a t i o n ) P r o j D i v s n A c t i v i t y O p e r a t n L o c U n i t U n i t s S t a r t E n d C r e w E s t F o r e C r e u C r e u C r e u E s t F o r e C r e u C r e u E s t C o d e C o d e Name Name tt H e a s t h i s D a t e D a t e S i z e C r e u c a s t Reg OT OT C r e u c a s t R B Q OT E q u i p Rep H r s C r e u H r s H r s H r s S C r e u S S S x x x x X X X X X X H r s T D C I .5) ce.oi S T D T D E q p E q p l E q p l E q p l E q p B E q p B Eqp5 E s t F o r B t l a t l E s t F o r B S u b S u b E s t X F o r B T D t l T o t l U a r M e t h o d F o r B Name H r s S To Name H r s S T o M a t l C a s t S T o S u b c a s t H r s $ T o T o t a l C o m p l t c a s t H r s Com i t i s n c e c a s t T D D a t e T D D a t a s f l a t l • a t e C t r Sub T D D a t e S T o t l T D S T o S S S S S D a t e Figura 27 A c t i v i t y - Operation Data C o l l e c t i o n F i l a S t r u c t u r e KJ Data Tranaformatlon r i a l d a ( C r e a t e c u r r a n t S v a l u a r e c o r d s f r o m p a s t a c t i v i t i e s ) ( T h e s e f i e l d s t o be a d d e d t o a r c h i v e d f i e l d s u h a n c r e a t i n g n e u r e c o r d s f r o m o l d d a t a R e c o r d D a t e o f P r o d u c t i v i t y U n i t E q u i p m e n t E q u i p U n i t M a t e r i a l S u b - T o t a l P u D a t e C o s t ( p a s t ) C o s t P r o d u c t i v i t y C o s t P u P <J C o n t a c t o r LS+ES+MS+SS A d j u s t m e n t m h s / u n i t P u E h r s / u n i t E S / u n i t (1 S / u n i t PU S S / u n i t I / u n i t Figure SB Data Tranaformatlon F i l a S t r u c t u r e - 128 -5.2.4 A c t i v i t y Data C o l l e c t i o n Summary F i l e The A c t i v i t y Data C o l l e c t i o n Summary F i l e , as the name i m p l i e s , i s simply a c o m p i l a t i o n of a l l cumulative r e c o r d s f o r each of the o p e r a t i o n s o f an a c t i v i t y . T h i s would be a good v e h i c l e f o r upper management t o compare o r i g i n a l estimate v e r s u s p r e s e n t f o r c a s t expenditures f o r a l l f i e l d s of i n t e r e s t . Those t h a t don't compare f a v o r a b l y are t o be h i g h l i g h t e d i n the form of an ex c e p t i o n r e p o r t and addressed t o the managers r e s p o n s i b l e . 5.2.5 P r o j e c t Data C o l l e c t i o n F i l e Summary T h i s f i l e i s i d e n t i c a l t o the above except t h a t i t i s a c o m p i l a t i o n of a l l the summarized a c t i v i t i e s o f a p r o j e c t . 5.2.6 A r c h i v e d Data C o l l e c t i o n F i l e T h i s f i l e i s s t o r e d with other f i n i s h e d p r o j e c t f i l e s and c o n t a i n s r e c o r d s of p r o j e c t s , a c t i v i t i e s , and o p e r a t i o n s f o r f u t u r e r e f e r e n c e . At completion o f the p r o j e c t , i t i s ve r y important t o up-date the "method" f i e l d i n a l l r e c o r d s t o ensure t h a t the methods used and c o n d i t i o n s encountered are recorded. The method f i e l d s w i l l be memo f i e l d s i n the database thus e n a b l i n g paragraphs t o be w r i t t e n d e s c r i b i n g a p p l i c a b l e f a c t s and f a c t o r s . These methods are then t o be c r o s s t a b u l a t e d with a - 129 -photo album or v i d e o tape l i b r a r y t o show the d e t a i l s of the a c t i v i t y - o p e r a t i o n i n the d e s c r i p t i o n . 5 . 2 . 7 New E s t i m a t i n g and Tendering F i l e s In the process of e s t i m a t i n g and t e n d e r i n g f o r a new p r o j e c t , h i s t o r i c a l data from p r e v i o u s l y a r c h i v e d p r o j e c t s i s now r e q u i r e d . One can e a s i l y s o r t through the database f o r jobs t h a t c o n t a i n a WBS s i m i l a r t o t h a t r e q u i r e d by the new p r o j e c t . Once s e l e c t e d , the e s t i m a t o r c o p i e s the p r e v i o u s WBS s t r u c t u r e (the f i e l d names) t o the e s t i m a t i n g module. E d i t i n g the WBS s t r u c t u r e t o e x a c t l y f i t the new p r o j e c t i s the next s t e p . With the s o r t and e d i t f i n i s h e d , the s t r u c t u r e of the estimate i s now e s t a b l i s h e d . The process of e s t i m a t i n g r e q u i r e s t h a t c o s t s be c a l c u l a t e d f o r l a b o r , equipment, and m a t e r i a l f o r each of the a c t i v i t i e s and o p e r a t i o n s t o be encountered i n the p r o j e c t . I f a company has p r e v i o u s l y performed the work i n qu e s t i o n , the a r c h i v e d r e c o r d s of p r o d u c t i v i t y ( u n i t s / hour) a d j u s t e d f o r the pr e s e n t s i t e c o n d i t i o n s ( d i f f i c u l t y f a c t o r ) and m u l t i p l i e d by the q u a n t i t y of u n i t s and by the present h o u r l y r a t e s g i v e a reasonably a c c u r a t e estimate of the c o s t s t o be i n c u r r e d i n performing the work. - 130 -5.2.8 Data Tr a n s f o r m a t i o n F i l e (see f i g u r e 28) T h i s d a t a f i l e i s u s e f u l i n the process of t r a n s f o r m i n g the manpower and equipment p r o d u c t i v i t i e s achieved i n a r c h i v e d p r o j e c t s t o v a l u e s t h a t can be achieved on the p r e s e n t p r o j e c t . The parameters i n v o l v e d w i l l be s i t e c o n d i t i o n s , weather c o n d i t i o n s , c o n g e s t i o n between t r a d e s and workmen, m a t e r i a l s t o r a g e space, r a t e of p r o d u c t i o n r e q u i r e d , and overtime r e q u i r e d . A numerical m u l t i p l i c a t i o n f a c t o r needs t o be assigned t h a t w i l l equate t h a t past p r o d u c t i v i t y t o the estimated p r o d u c t i v i t y f o r every a c t i v i t y - o p e r a t i o n . Costs can be t r a n s l a t e d by a p p l y i n g the i n f l a t i o n r a t e experienced i n the elapsed time between p r o j e c t s . S u b c o n t r a c t o r c o s t s would u s u a l l y be quoted but c o u l d be f a c t o r e d and estimated f o r s m a l l scope work. Documentation of the t r a n s f o r m a t i o n process i s v e r y important to the c o n f i d e n c e l e v e l of the estimate. T h i s documentation i n the form of r e c o r d source, date, f a c t o r , e s t i m a t o r , e t c . p r o v i d e the c h i e f e s t i m a t o r with the means t o check the work of h i s s u b o r d i n a t e s . The f i n a l process i n the estimate would then be the e x t e n s i o n and summation of c o s t s , summarized by o p e r a t i o n , a c t i v i t y , and p r o j e c t . - 131 -5.2.9 P l a n n i n g and S c h e d u l i n g F i l e s Assuming the estimate i s s u c c e s s f u l , the process i s now s h i f t e d t o the p r o j e c t p l a n n i n g and s c h e d u l i n g phase. The estimate i s a r c h i v e d , s u p e r f l u o u s i n f o r m a t i o n s t r i p p e d away and the estimate r e c o r d s are now a v a i l a b l e f o r use by the p r o j e c t management team to d e s i g n and schedule the d e t a i l s of the a c t i v i t i e s . 5.3 D a t a f i l e Design U s i n g a M u l t i d i m e n s i o n a l Spreadsheet In t h i s s e c t i o n , an i n f o r m a t i o n system with s i m i l a r content but with a d i f f e r e n t arrangement of the data h i e r a r c h y i s d e s c r i b e d . The purpose of t h i s d i s c u s s i o n i s t o show the e f f e c t s o f a d i f f e r e n t data h i e r a r c h y on the system. The software s e l e c t e d f o r comparison was reviewed i n the l i t e r a t u r e -software search and i s c a l l e d TM1. The software i s a m u l t i d i m e n s i o n a l spreadsheet a l s o c a l l e d a t a b l e manager. I t has the c a p a c i t y of up t o e i g h t "dimensions" per spreadsheet. F i g u r e 29 shows a l i s t i n g of the dimensions a c r o s s the top and a l i s t of headings under each dimension. Since the t a b l e (spreadsheet) d i s p l a y e d on the monitor i s onl y two dimensional, o n l y two of the a v a i l a b l e dimensions can be d i s p l a y e d i n mat r i x form a t one time. Of the dimensions not i n c l u d e d i n the two dimensional matrix, one of the headings of each dimension i s s e l e c t e d as a c t i v e and i s denoted by i t s l i s t i n g i n row two. The a c t i v e heading w i l l be - 132 -s e l e c t e d and the v a l u e s t h a t are dependent on t h a t heading element w i l l be d i s p l a y e d when the t a b l e i s c a l l e d w i t h the "view" command. a c t i v e heading i d e n t i f i e d — A c t i v i t y Operatn Loc Resource Phase D e s c r i p t Beams Shore F t g 1 Labor * l i n * * c o l * <-Foo t i n g s Shore F t g 1 Labor E s t . t o t a l U n i t s Columns Shore tower 2 Equip Feast t o t l MHrs Beams Prefab form 3 M a t e r i a l % complete Costs Wings E r e c t forms 4 Subctr To date t o t a l B a r r i e r s Free form 5 Overhead Decking Rebar 6 T o t a l T o t a l P Tension Concrete PT s t r e s s i n g Form remove T o t a l F i g u r e 29 M u l t i d i m e n s i o n a l Spreadsheet Screen Showing  Dimensions Across the Top and Headings W i t h i n the Dimension  Below. The symbols * l i n * and * c o l * denote the dimensions which w i l l occupy the rows and columns of the matrix. In f i g u r e 29, the f o l l o w i n g headings are a c t i v e f o r each dimension: Heading: Beams Shore F t g 1 Labor * l i n * * c o l * The r e s u l t i s a t a b u l a t i o n of the v a l u e s of "Phase" v e r s u s " D e s c r i p t " f o r a c t i v i t y = beam, o p e r a t i o n = shore f o o t i n g , l o c a t i o n = 1, resource = l a b o r . - 133 -The r e s u l t i n g spreadsheet i s shown i n f i g u r e 30. A c t i v i t y = Beams Operatn = Shore f o o t i n g s L o c a t i o n = 1 Resource = l a b o r D e s c r i p t o r - > Manhours Costs Methods Phase I Estimate t o t a l 35 $700. Concrete s p r e a d f o o t i n g F o r e c a s t t o t a l 30 $600. Timber 12 x 12 f o o t i n g % complete 90% P r o j e c t e d t o t a l 32.5 $650. Timber 12 x 12 f o o t i n g F i g u r e 30 M u l t i d i m e n s i o n a l Spreadsheet Screen Showing Phase  Versus D e s c r i p t i o n f o r the I d e n t i f i e d A c t i v i t y , O p e ration,  L o c a t i o n , and Resource. T h i s format would be of i n t e r e s t i n the m o n i t o r i n g phase of the p r o j e c t when comparisons from estimate t o c u r r e n t f o r e c a s t to a c t u a l would be r e q u i r e d . The p o i n t s t o be mentioned r e g a r d i n g the advantages of the f o r e g o i n g data s t r u c t u r e are as f o l l o w s : 1. A spreadsheet format i s very good at comparing and c o n t r a s t i n g l i k e v a l u e s . 2. The e i g h t t i e r h i e r a r c h y allows the database t o appear l e s s crowded on the screen. Fewer headers need t o be d i s p l a y e d a t once. Yet a l l are a v a i l a b l e . - 134 -3. The TM1 system does not s t o r e the v a l u e s i n the spreadsheet, i t s t o r e s them i n t a b l e s . In the t a b l e t h e r e i s one unique v a l u e f o r the union of a l l combinations of a l l e i g h t dimensions. 4. The spreadsheet above i s composed of formulae t h a t i d e n t i f y the t a b l e s , headings and c e l l s from which t o r e c a l l data v a l u e s . S i n c e the data i s independent of the spreadsheet, the spreadsheet i s then a template i n which t o import i n f o r m a t i o n from any dimension heading t h a t i s a p p r o p r i a t e . To change the data, simply change the name of one of the headings of the spreadsheet. To i l l u s t r a t e t h i s p o i n t , change the o p e r a t i o n from "shore f o o t i n g s " t o "concrete", see f i g u r e 31. A c t i v i t v = Beams Operatn = Concrete L o c a t i o n = 1 Resource = l a b o r D e s c r i p t o r Phase Estimate t o t a l F o r e c a s t t o t a l % complete P r o j e c t e d t o t a l Manhours Costs Methods 100 50 100% 65 $2000. $1000. $1300. Crane and bucket Pump Pump Fi g u r e 31 M u l t i d i m e n s i o n a l Spreadsheet: Phase Versus D e s c r i p t o r f o r the I d e n t i f i e d Parameters - 135 -When the spreadsheet i s r e c a l c u l a t e d , the v a l u e s are c o p i e d from the a p p r o p r i a t e t a b l e and the spreadsheet template i s r e f r e s h e d w i t h the new v a l u e s . Now l e t s c r e a t e a spreadsheet so t h a t the dimension " l o c a t i o n " w i l l be s e l e c t e d t o f i l l column headings and the dimension " d e s c r i p t o r " w i l l be s e t so t h a t " c o s t s " are a c t i v e . I t w i l l appear as shown i n f i g u r e 32. A c t i v i t y = Beams Operatn = Concrete D e s c r i p t = Costs Resource = l a b o r L o c a t i o n —> 1 2 3 Phase Estimate t o t a l $2000. $2500. $5000 F o r e c a s t t o t a l $1000. $2500. $2500 % complete 100% 80% 50% To date t o t a l $1300. $2000. $1200. P r o j e c t e d t o t a l $1300. $2500. $2400 % V a r i a n c e +30% 0% -4% F i g u r e 32 M u l t i d i m e n s i o n a l Spreadsheet, Phase Versus  L o c a t i o n f o r the I d e n t i f i e d Parameters. N o t i c e t h a t w i t h t h i s spreadsheet, some rows have been added t o c a l c u l a t e the p r o j e c t e d t o t a l and the % v a r i a n c e u s i n g t y p i c a l spreadsheet c a p a b i l i t i e s . T h i s database / spreadsheet c a p a b i l i t y g i v e s the user a f r e e hand i n s e l e c t i n g the data and s t r u c t u r i n g the output. As can be seen, t h i s software p r o v i d e s a database which can be r e c a l l e d t o f i l l c e l l s of a spreadsheet and then - 136 -manipulated w i t h r e l a t i v e ease t o the format d e s i r e d . I t i s a u s e f u l t o o l . 5.4 Software Command (Menu) S t r u c t u r e The a b i l i t y o f a software package t o i n t e r a c t w i t h the us e r i s always an important i s s u e . The ease (or d i f f i c u l t y ) which the user f i n d s when t r y i n g t o operate the system i s every b i t as important as the f u n c t i o n s c o n t a i n e d w i t h i n the system. The menu of system commands i s the road map o f f e r e d by the system d e s i g n e r t o guide the user t o the a p p r o p r i a t e f u n c t i o n s and f i l e s . A menu of f u n c t i o n s and commands has been i n c l u d e d i n the appendix t o p r o v i d e an example of the d e t a i l r e q u i r e d i n the des i g n of a c o n s t r u c t i o n i n f o r m a t i o n system. The menu i s i n c l u d e d i n Appendix 1 i n order t o minimize c o n f u s i o n w i t h the d i f f e r e n t numbering system found i n the "general p l a n n i n g model" which has a l e s s e r l e v e l of d e t a i l . For f i n a l system d e s i g n , which i s not p a r t of the scope o f t h i s r e s e a r c h , one would match the numbering schemes of the model t o the menu. - 137 -CHAPTER 6. TESTING THE MODEL, THE SEATTLE CUT AND COVER TUNNELING EXAMPLE 6.0 I n t r o d u c t i o n The p l a n n i n g a l g o r i t h m d e t a i l e d i n Chapter 4 was s p e c i f i c t o co n c r e t e m u l t i s p a n b r i d g e c o n s t r u c t i o n . In t h i s c h apter another form of r e p e t i t i o u s c o n c r e t e c o n s t r u c t i o n i s examined i n terms of p l a n n i n g requirements. Tunnels and b r i d g e s have some i n t e r e s t i n g d i f f e r e n c e s and s i m i l a r i t i e s . Obviously, one i s below ground and the o t h e r above. T h i s does pose d i f f e r e n c e s i n the techniques r e q u i r e d t o c o n s t r u c t the a c t i v i t i e s . However, the p r o f i l e d i f f e r e n c e does not pose d i f f e r e n c e s t o the p l a n n i n g methods u t i l i z e d . A major s i m i l a r i t y l i e s i n the f a c t t h a t both s t r u c t u r e s are t r a n s p o r t a t i o n c o r r i d o r s and as such are l i n e a r and r e p e t i t i o u s i n nature and ab l e t o u t i l i z e the b e n e f i t s of l i n e a r sequencing i n t h e i r c o n s t r u c t i o n . Because the t u n n e l p r o j e c t i s s i m i l a r y e t d i f f e r e n t from the b r i d g e p r o j e c t , i t i s a good candidate f o r t e s t i n g o f the p l a n n i n g model. E v a l u a t i o n of the g e n e r a l p l a n n i n g a l g o r i t h m v i a the S e a t t l e Cut and Cover Tunnel P r o j e c t case study y i e l d s some u s e f u l o b s e r v a t i o n s and recommendations r e g a r d i n g : 1. the robustness of the concepts and f u n c t i o n s of the model; and 2. the p o r t a b i l i t y of the model t o another type of p r o j e c t . - 138 -U s e f u l v i e w p o i n t s f o r e v a l u a t i o n The f o l l o w i n g v i e w p o i n t s are u s e f u l i n e v a l u a t i o n o f the p l a n n i n g model v i s - a - v i s the Tunnel P r o j e c t case study: 1. What are the a d d i t i o n a l a c t i v i t y p l a n n i n g problems presented by the t u n n e l p r o j e c t ? 2. Are the f u n c t i o n s and c a p a b i l i t i e s r e q u i r e d f o r c u t and cover t u n n e l p l a n n i n g a v a i l a b l e i n the p l a n n i n g model? 3. Are a d d i t i o n a l g r a p h i c a l techniques r e q u i r e d t o permit v i s u a l i z a t i o n o f the e x c a v a t i o n process? 4. What a d d i t i o n a l bodies o f knowledge are r e q u i r e d i n the p l a n n i n g process? 5. Determine the va l u e of the b r i d g e p l a n n i n g a l g o r i t h m s f o r p l a n n i n g o t h e r types o f c o n s t r u c t i o n p r o j e c t s . Are t h e r e p r i n c i p l e s behind the al g o r i t h m s t h a t are u s e f u l f o r the whole scope of c o n s t r u c t i o n planning? With the above viewpoints i n mind we e n t e r the General P l a n n i n g Model as per the flow c h a r t i n 4.0, f i g u r e 9 f o r the s p e c i f i c a p p l i c a t i o n o f "Cut and Cover Tunneling". I t i s not the i n t e n t t o proceed step by step through the model. D i s c u s s i o n i s l i m i t e d here t o the d i f f e r e n c e s between p l a n n i n g f o r b r i d g e s and p l a n n i n g f o r t u n n e l s . The numbering system used f o r Chapter 6 c o i n c i d e s w i t h those used i n the Chapter f o u r headings. Not a l l Chapter f o u r s e c t i o n s are d i s c u s s e d here, o n l y those of i n t e r e s t t o the t e s t i n g of the pl a n n i n g system. - 139 -6.1 P r o j e c t : S e a t t l e Cut and Cover Tunnel 6.1.1 P r o j e c t Award: B r i e f D e s c r i p t i o n o f the P r o j e c t . The c u t and cover t u n n e l o b s e r v a t i o n s are based on work done by SCI C o n t r a c t o r s Inc. i n 1987 on a 800 f o o t s e c t i o n o f the Downtown S e a t t l e Tunnel P r o j e c t . The s i t e f o r the t u n n e l was a th r e e b l o c k l e n g t h of Pine S t r e e t on an e i g h t y f o o t r i g h t - o f - w a y between Westlake and Convention Center s t a t i o n s . The c o n t r a c t c a l l e d f o r the c l o s u r e of Pine S t r e e t f o r a s i x month c o n s t r u c t i o n p e r i o d , removal or support o f the e x i s t i n g u t i l i t i e s , s h o r i n g of the tu n n e l w a l l s as per c o n t r a c t o r design, and e x c a v a t i o n t o 60 f e e t below s t r e e t grade. The c o n t r a c t o r e l e c t e d t o d r i l l 3 0" h o l e s a t 8 f o o t i n t e r v a l s , p l a c e s t e e l H s e c t i o n p i l e s i n the d r i l l e d h o l e s and b a c k f i l l the p i l e s with a weak " l e a n mix" con c r e t e . During the e x c a v a t i o n p r o c e ss, 4" by 12" l a g g i n g was p l a c e d between p i l e s t o r e t a i n the s o i l . S t e e l walers and s t r u t s were welded t o the p i l e s t o p r o v i d e l a t e r a l b r a c i n g t o the s h o r i n g system. The r e i n f o r c e d c o n c r e t e t u n n e l s t r u c t u r e has a r e c t a n g u l a r s e c t i o n 38 f e e t wide and 16 f e e t high, i n s i d e dimensions. I t was designed, formed, and poured i n f i f t y f o o t segments comprised of 5 f o o t f l o o r s l a b , 3 f o o t t h i c k w a l l s and 5 f o o t r o o f . - 140 -6.1.2 P r o j e c t Work Breakdown S t r u c t u r e (WBS) The work breakdown s t r u c t u r e f o r the tu n n e l s u b - p r o j e c t r e p r e s e n t e d as f o l l o w s : Pine S t r e e t Tunnel S t r u c t u r e P i l e s and b r a c i n g systems s u b m i t t a l S o l d i e r p i l e s S u r f a c e u t i l i t y E x c a v a t i o n Deep u t i l i t i e s as encountered with the e x c a v a t i o n Lagging B r a c i n g wales and s t r u t s Working f l o o r Base s l a b C l e v e l s t r u t s and walers Walls Roof Remove B and A l e v e l s t r u t s and walers B a c k f i l l S t r e e t r e s t o r a t i o n - 141 -6.1.3 Proj e c t C o n s t r a i n t s S i t e S p e c i f i c C o n s t r a i n t s The sequence of exca v a t i o n , l a g g i n g , and b r a c i n g had s i t e c o n d i t i o n and c o n t r a c t c o n s t r a i n t s imposed. In the case of the Pine S t r e e t Tunnel, the requirement was e x c a v a t i o n not allowed t o proceed deeper than 10 f e e t below the l a g g i n g nor deeper than 12 f e e t below the b r a c i n g . S i n c e the l a g g i n g equipment c o u l d not occupy the same space as the ex c a v a t i o n equipment, these two a c t i v i t i e s were c o n s t r a i n e d t o f o l l o w l e a p - f r o g sequencing t o reach the r e q u i r e d 60 f o o t depth. The b r a c i n g was g e n e r a l l y done on the same s h i f t as the l a g g i n g . See f i g u r e 33, s e c t i o n 6.1.5 f o r a time-space diagram t h a t i l l u s t r a t e s the sequence. Geometric C o n s t r a i n t s The confinement caused by t u n n e l i n g 60 f e e t deep with o n l y 38 f e e t of width imposes c o n s t r a i n t s on the c o n t r a c t o r ' s a b i l i t y t o move equipment and formwork i n any d i r e c t i o n o t h e r than the d i r e c t i o n of the t u n n e l i n g . The f o l l o w i n g a c t i v i t i e s on the Pine S t r e e t Tunnel s u b - p r o j e c t , Working f l o o r , Base s l a b , C l e v e l b r a c i n g , Walls, and Roof e x h i b i t e d f i n i s h - s t a r t r e l a t i o n s h i p s f o r u n i t a c t i v i t i e s . The r e s u l t i s a l i n e a r a c t i v i t y sequence where an a c t i v i t y must f o l l o w i t s predecessor i n both time and space. See f i g u r e 34. - 142 -T h e t u n n e l s u b - p r o j e c t , a s a w h o l e , s t e p p e d f o r e w a r d i n a c e n t i p e d e s t y l e o f m o v e m e n t w h e r e o n e a c t i v i t y f i n i s h e d , t h e e q u i p m e n t o r f o r m w o r k w a s m o v e d f o r e w a r d , a n d t h e s u c c e e d i n g a c t i v i t y e q u i p m e n t o r f o r m w o r k w a s m o v e d i n t o t h e l o c a t i o n n e w l y v a c a t e d . 6.1.5 Model The P r o j e c t T h e S u b m i t a l , P i l e s , a n d U t i l i t i e s a c t i v i t i e s a r e n o t o f i n t e r e s t t o t h i s d i s c u s i o n . F i g u r e 3 3 s h o w s a t i m e - s p a c e d i a g r a m t h a t i l l u s t r a t e s t h e s e q u e n c e f o r t h e E x c a v a t i o n , L a g g i n g , a n d B r a c i n g a c t i v i t i e s o f t h e s u b - p r o j e c t . F i g u r e 3 3 T i m e - S p a c e D i a g r a m : E x c a v a t i o n , L a g g i n g , a n d B r a c i n g A c t i v i t i e s f o r S u b - p r o i e c t T u n n e l - 143 -L o c a t i o n (50' Segments) 2 4 6 8 10 12 14 16 18 20 22 24 Days F i g u r e 34 Time-Space Diagram: Base s l a b . C L e v e l s t r u t . Walls, and Roof A c t i v i t i e s f o r S u b - p r o i e c t Tunnel The above diagrams show the sequences as c o n s t r a i n e d by the c o n d i t i o n s mentioned i n s e c t i o n 6.1.3. They a l s o show the f i r s t rough pass a t e s t i m a t i n g r e l a t i v e d u r a t i o n s . In a d d i t i o n t o the m o d e l l i n g techniques shown i n 4.1.5, t h i s Tunnel case study p o i n t s out the need f o r a p r o f i l e drawing showing the c o n s t r u c t i o n sequence. F i g u r e 35 shows the sequence drawing f o r the e a r l y stages of t u n n e l a c t i v i t y p l a n n i n g . T h i s sequence drawing i s p a r t i c u l a r l y u s e f u l f o r t u n n e l p l a n n i n g i n t h a t i t p r o v i d e s a method f o r v i s u a l i z a t i o n of the e x c a v a t i o n p r o c e s s . - 145 -6.1.7 T a r g e t D u r a t i o n B a r c h a r t Schedule Showing T a r g e t D u r a t i o n The b a r c h a r t i n f i g u r e 3 6 shows t a r g e t d u r a t i o n s f o r t u n n e l segments 20 t o 8 as per the d i s c u s s i o n i n chapter 4.1.7. These segments are c o n s t r a i n e d by m i l e s t o n e s t h a t a l l o w c o n s t r u c t i o n t o take p l a c e on c i t y s t r e e t s from May 1 t o November 1, 1987. T h i s then becomes the c r i t e r i a f o r e s t a b l i s h i n g the s u b - p r o j e c t t a r g e t d u r a t i o n . •-Submittal *-Soldier p i l e s • - U t i l i t i e s -*-Excavate •-Lagging •-Bracing struts •Working floor • Base slab •-Walls * Roof * S t r u t s — • B a c k f i l l - * Streets* 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Weeks F i g u r e 3 6 Tunnel S u b p r o i e c t Barchart Showing Target Durations - 146 -The l o g i c behind the t a r g e t d u r a t i o n b a r c h a r t i s b r i e f l y d e s c r i b e d as f o l l o w s : 1. I d e n t i f y the a c t i v i t y or a c t i v i t y t h a t r e q u i r e the l o n g e s t d u r a t i o n s per r e p e t i t i o n . For t h i s t u n n e l p r o j e c t , the "pour r o o f " a c t i v i t y i s v e r y l i k e l y t o r e q u i r e the l o n g e s t d u r a t i o n i f f o r no o t h e r reason than i t must cure f o r 3 to 4 days p r i o r t o s t r i p p i n g . F i g u r e 34 r e f l e c t s a l a r g e d u r a t i o n f o r Roof i n t h a t the s l o p e of the p r o d u c t i o n l i n e f o r r o o f i s f l a t t e r t h a t the o t h e r o p e r a t i o n s . 2. Estimate the s t a r t - u p d u r a t i o n s of the a c t i v i t i e s p r e c e d i n g the "pour r o o f " a c t i v i t y . S i n c e the space c o n s t r a i n t mentioned above c o n f i n e s the a c t i v i t i e s t o f i n i s h - s t a r t precedence l o g i c , the f i r s t r e p e t i t i o n of each a c t i v i t y i s on the c r i t i c a l path a t l e a s t u n t i l i t s s u c e s s o r i s allowed t o begin. P l o t the f i r s t r e p e t i t i o n s of these a c t i v i t i e s . 3. Estimate the f i n i s h d u r a t i o n of the a c t i v i t i e s succeeding "pour r o o f " . The l a s t of these a c t i v i t i e s w i l l be on the c r i t i c a l path. P l o t the l a s t r e p e t i t i o n s of these a c t i v i t i e s . 4. The time remaining between the predecessor and s u c c e s s o r a c t i v i t i e s of "pour r o o f " i s the maximum t a r g e t d u r a t i o n allowed f o r t h a t l o n g e s t d u r a t i o n a c t i v i t y . - 147 -5. The d e r i v e d t a r g e t d u r a t i o n f o r "pour r o o f " can now be d i v i d e d by the number of pour segments t o get the maximum u n i t a c t i v i t y t a r g e t d u r a t i o n . The a v a i l a b l e d u r a t i o n f o r "pour r o o f " i s approximated on the b a r c h a r t by the time remaining between c o n s t r a i n i n g a c t i v i t i e s (13 weeks). The r e q u i r e d p r o d u c t i o n r a t e i s then 12 segments / 13 weeks = + - l segments per week. 6.1.8 S u b p r o j e c t C o n t i n u i t y ? L i n e a r S c h e d u l i n g Required? The s u b j e c t o f c o n t i n u i t y and l i n e a r s c h e d u l i n g was p r e s e n t i n the b r i d g e p r o j e c t model but onl y a t the a c t i v i t y l e v e l f o r sequencing o p e r a t i o n s . As i n d i c a t e d i n 6.1.3, l i n e a r sequencing may be p o s s i b l e a t the s u b p r o j e c t l e v e l f o r a group of a c t i v i t i e s . The sequence Base s l a b , C s t r u t , W alls, and Roof e x h i b i t l i n e a r t r a i t s i n t h a t one must f o l l o w i t s predecessor i n time and space. The g e n e r a l p l a n n i n g model i s d e f i c i e n t i n t h i s regard as i t o n l y addresses l i n e a r s c h e d u l i n g f o r u n i t a c t i v i t i e s i n sequence from one l o c a t i o n t o the next. To accomodate t h i s a d d i t i o n a l c a p a b i l i t y , the a l g o r i t h m must be amended t o i n c l u d e l i n e a r s c h e d u l i n g a t the s u b - p r o j e c t l e v e l . The change i s shown to be necessary f o r t u n n e l a c t i v i t i e s but i t i s a l s o a v a l u a b l e a d d i t i o n t o a g e n e r a l p l a n n i n g model. F i g u r e 37 shows a r e v i s i o n t o the g e n e r a l p l a n n i n g flow c h a r t t o make these p r o j e c t l e v e l changes. - 148 -M o d i f i c a t i o n s t o the A c t i v i t y P l a n n i n g A l g o r i t h m P r o j e c t Model the P r o j e c t C o n s t r a i n t s Network Ba r c h a r t Target Durations Q u a n t i t i e s Rate t a b l e s C o n s t r u c t i o n Sequence Drawing C o n t r a c t Duration S p e c i f i e d ? Target Duration A c t i v i t i e s Require L i n e a r and Continuous Scheduling? Input L i n e a r C o n s t r a i n t s Output: U n i t A c t i v i t y D uration Crew C y c l e Duration M a t r i x Crew Schedule P r o j e c t L e v e l P r e l i m i n a r i e s Completed. Proceed t o the A c t i v i t y L e v e l of Pl a n n i n g . (This now t i e s i n t o the g e n e r a l p l a n n i n g a l g o r i t h m a t 4.2) F i g u r e 37 P r o j e c t L e v e l R e v i s i o n t o the General P l a n n i n g Model - 149 -6.1.8.1 C y c l e R e c o g n i t i o n As shown i n the c o n s t r u c t i o n sequence drawing and as mentioned under c o n s t r a i n t s above, the a c t i v i t i e s i n the t u n n e l s u b p r o j e c t f o l l o w each ot h e r i n s t e p . I t can be s a i d t h a t the a c t i v i t i e s i n v o l v e d are " i n t e r r e l a t e d " and i n the c o n t e x t of t h i s t h e s i s , t h a t means the a c t i v i t i e s are c o n s t r a i n e d by the d u r a t i o n of the p r e c e e d i n g a c t i v i t y . The d u r a t i o n of the a c t i v i t i e s may now be s y n c r o n i z e d by p r o v i d i n g a standard c y c l e d u r a t i o n f o r the a c t i v i t i e s t o f o l l o w i n unison. T h i s c y c l e i s a g a i n c a l l e d the " u n i t a c t i v i t y c y c l e " , but t h i s case i t r e p r e s e n t s the c y c l e of a s e r i e s of a c t i v i t i e s . In g e n e r a l , the slowest a c t i v i t y s e t s the c y c l e d u r a t i o n . Another way of t h i n k i n g about t h i s i s t h a t the slowest a c t i v i t y deserves the most a t t e n t i o n t o speed i t t o the p r o d u c t i o n r a t e of the o t h e r a c t i v i t i e s . I t then becomes e f f i c i e n t , i n terms of s u b p r o j e c t e a r l y f i n i s h , f o r a l l a c t i v i t i e s t o f o l l o w a t the same c y c l e d u r a t i o n . I f the l a s t a c t i v i t y or a c t i v i t i e s have a s h o r t e r u n i t a c t i v i t y c y c l e time, they then c o u l d be allowed t o s t a r t l a t e r as they have f l o a t i n t h e i r schedule. - 150 -6.1.8.2 C y c l e Design E f f i c i e n c i e s E f f i c i e n c i e s from the above l i n e a r sequencing can be r e a l i z e d i f i t i s f e a s i b l e and p r a c t i c a l t o d e s i g n a u n i t a c t i v i t y c y c l e d u r a t i o n t h a t i s the same f o r a l l a c t i v i t i e s i n the s u b - p r o j e c t . The c y c l e d e s i g n e f f i c i e n c i e s are a f u n c t i o n of the f a v o r a b l e rhythm t h a t a l l o w s the p r o j e c t t o r o l l on due t o s e l f - g e n e r a t e d momentum. As d i s c u s s e d i n 4.2.3, a t a n g i b l e b e n e f i t can be o b t a i n e d from the e s t a b l i s h m e n t of a rhythm t h a t maximizes the p r o d u c t i v i t y of the crews. For the case study i n q u e s t i o n , the problem a r i s e s i n t h a t the d u r a t i o n f o r " r o o f pour" i s s i g n i f i c a n t l y l o n g e r than the d u r a t i o n of f l o o r s l a b or w a l l pour. T h i s s i t u a t i o n i s i n h e r e n t i n a r o o f or supported s l a b s t r u c t u r e because of the c u r i n g time r e q u i r e d b e f o r e s t r i p p i n g can be allowed. Both the f l o o r s l a b and the w a l l s r e q u i r e much l e s s cure time p r i o r t o s t r i p p i n g . The q u e s t i o n then becomes "Does our a c t i v i t y d e s i g n system allow the p l a n n e r the f l e x i b i l i t y t o l i s t and p r i c e the v a r i o u s a l t e r n a t i v e s t h a t c o u l d decrease the a c t i v i t y d u r a t i o n ? " The a c t u a l c o s t s of the a c t i v i t y " r o o f " w i l l be analyzed i n the a c t i v i t y and subtrade o p e r a t i o n l e v e l s of the p l a n n i n g model. One a d d i t i o n a l q u e s t i o n needs t o be addressed from the p r o j e c t l e v e l , "Is i t a v i a b l e s o l u t i o n t o share the crews between the w a l l a c t i v i t y and the r o o f a c t i v i t y ? " For t h i s a l t e r n a t i v e , the w a l l s would be slowed because of crew t i m e - s h a r i n g . The r o o f d u r a t i o n , f o r which t i m e l y progress i s c r i t i c a l , may not be a f f e c t e d because the w a l l work c o u l d c o n c e i v a b l y happen d u r i n g - 151 -the roof curing time. This i s another example of a great number of crew scheduling schemes that can be imagined and implemented. For each s i t u a t i o n , i n t u i t i v e solutions can be devised that maximize the useage of the manpower and equipment for the a c t i v i t i e s at hand. The interconnection of a c t i v i t i e s and operations with useful cycles of work can be termed cycle recognition and i s an important part of a c t i v i t y design. 6.1.8.3 Crew Cycle Before t h e o r e t i c a l e f f i c i e n c i e s of crew p r o d u c t i v i t i e s can be real i z e d , the unit a c t i v i t i e s have to be broken down to the operation (sub-trade) l e v e l , where sub-trade crews must also experience a favorable cycle of r e p e t i t i o n . This concept, as expressed i n 4.2 .3, i s c a l l e d "crew cycle duration". When a crew i s shared between d i f f e r e n t a c t i v i t i e s , such as walls and roofs i n the example above, and maintains a constant crew cycle, t h i s can be c a l l e d " m u l t i - a c t i v i t y crew scheduling". 6.1.8.4 M u l t i - a c t i v i t y Crew Scheduling M u l t i - a c t i v i t y crew scheduling can best be expressed by an example, see figure 38. - 152 -L o c a t i o n and A c t i v i t y N. Wall 2 S. Wall 2 Roof bulkhead 1 Roof s o f f i t 1 N. Wall 1 S.Wall 1 Form Form Rebar Form Rebar Concrete Form Rebar Concrete S t r i p Form Rebar Concrete S t r i p Form Rebar Concrete S t r i p Days F i g u r e 38 Time-space Diagram: M u l t i - a c t i v i t y Crew Sch e d u l i n g The t h e o r y expressed here i s i d e n t i c a l t o t h a t of chapter 4.2.4, l i n e a r c o n s t r a i n t i n p u t , except t h a t more than one a c t i v i t y i s i n v o l v e d . With the above schedule, a l l of the i n v o l v e d crews r o t a t e from a c t i v i t y t o a c t i v i t y , i n s t e a d of from l o c a t i o n t o l o c a t i o n as per 4.2.4. From the a c t i v i t y p l a n n i n g p o i n t of view the problem i s t o design the c o n s t r u c t i o n procedures t o c o n t a i n the same amount of crew hours so t h a t a standard crew c y c l e with a constant crew s i z e works e f f i c i e n t l y . The t h e o r y i s u s e f u l . The a p p l i c a t i o n of the theory i s o b v i o u s l y c o n s t r a i n e d by s i t e c o n d i t i o n s and the s i m i l a r i t y between a c t i v i t i e s . - 153 -6 . 1 . 8 . 5 C o n t i n g e n c i e s W i t h l i n e a r s c h e d u l i n g , i t m u s t b e m e n t i o n e d t h a t i t ' s g r e a t e s t a s s e t w i l l t u r n i n t o i t ' s g r e a t e s t l i a b i l i t y i f s o m e o b s t a c l e s t a n d s i n t h e p a t h o f t h e c o n s t r u c t i o n o f t h e c h a i n o f a c t i v i t i e s . T h e p r e v i o u s l y m e n t i o n e d m o m e n t u m g e n e r a t e d b y t h e c h a i n w i l l t r a n s l a t e i n t o a c o s t l y s t a n d s t i l l i f a d e l a y i n o n e a c t i v i t y c a u s e s t h e c h a i n o f a c t i v i t i e s t o h a l t . A c o n t i n g e n c y p l a n w o u l d b e u s e f u l i n t h e e v e n t o f a n a c t i v i t y d e l a y . O n e m e a n s o f a c c o m p l i s h i n g t h i s i s b y u t i l i z i n g a n i g h t s h i f t t o o v e r c o m e u n f o r s e e n d e l a y s i n p r o d u c t i o n a n d t h u s k e e p i n g t h e l i n e a r s c h e d u l e o n t r a c k . 6 . 2 A c t i v i t y L e v e l P l a n n i n g A t t h i s l e v e l o n e a s s e s s e s t h e i n t e r d e p e n d e n c i e s b e t w e e n o p e r a t i o n s o f t h e s a m e a c t i v i t y . T h e r e l e v a n t p r o c e d u r e s a s p e r t h e g e n e r a l p l a n n i n g m o d e l a r e : 1 . C r e a t e a n d d e f i n e t h e a c t i v i t y . ( i ) WBS ( i i ) C o n s t r a i n t s ( i i i ) D e c i s i o n t r e e ( i v ) D i c t i o n a r y a n d c o d i n g s y s t e m . 2 . M o d e l t h e a c t i v i t y . - 154 -3 . L i n e a r a n d c o n t i n u o u s s c h e d u l i n g ? A l l t h e a c t i v i t i e s w i l l r e c e i v e t h i s a n a l y s i s . T h e r o o f a c t i v i t y i s s e l e c t e d h e r e f o r d i s c u s s i o n a s i t i s t h e m o s t d i f f i c u l t o f t h o s e a c t i v i t i e s i n t h e s e q u e n c e . 6.2.1 C r e a t e a n d D e f i n e t h e A c t i v i t y W o r k B r e a k d o w n S t r u c t u r e T h e f o l l o w i n g o p e r a t i o n s a p p e a r i n t h e w o r k b r e a k d o w n s t r u c t u r e o f " r o o f c o n s t r u c t i o n " : S h o r i n g S y s t e m ROOF CONSTRUCTION F o r m i n g S y s t e m R e b a r M a t e r i a l H a n d l i n g R e b a r P l a c e m e n t C o n c r e t e P l a c e m e n t S h o r e a n d F o r m R e m o v a l - 155 -C o n s t r a i n t s L i s t e d 1. Loading: 5 f o o t t h i c k r o o f equates t o (5 * 150pcf) Dead l o a d 50psf L i v e l o a d 800 p s f d e s i g n l o a d 2. Sequence i ) F l o o r and w a l l s must be done p r i o r t o r o o f c o n s t r u c t i o n . (Sub-project l e v e l ) i i ) A l l o p e r a t i o n s except rebar h a n d l i n g e x h i b i t f i n i s h -s t a r t r e l a t i o n s h i p s . 3. M a t e r i a l h a n d l i n g : Rebar i ) S i n c e no e n t r y t o the t u n n e l has y e t been c o n s t r u c t e d , the d e c i s i o n has been made t o begin t u n n e l l i n g a g a i n s t a bulkhead. T h i s has i m p l i c a t i o n s f o r m a t e r i a l h a n d l i n g systems i n t h a t no e n t r y f o r ground t r a n s p o r t a t i o n i s a v a i l a b l e a t the bulkhead end. i i ) No ground t r a n s p o r t a t i o n i s a v a i l a b l e from the d i g g i n g end f o r a c t i v i t i e s f o l l o w i n g base s l a b as access over the s l a b i s not p o s s i b l e . i i i ) Crane setups are a l s o l i m i t e d by the s t r e e t c o r r i d o r and the b u i l d i n g s on each s i d e . The a l l e y s and the c r o s s s t r e e t s are a v a i l a b l e f o r set-ups but not i n between. - 156 -D e c i s i o n t r e e S h oring i ) Many l i g h t 20 k i p towers. Heavy towers, beams and p l a t e g i r d e r s . systems i i ) i i i ) Wheeled tower assemblies. Form systems: i ) Plywood s k i n forms. i i ) S t e e l s k i n . Number of i ) One segments t o i i ) Two form a t once i i i ) Three M a t e r i a l h a n d l i n g Rebar i ) Drag rebar t r a i l e r t o bottom of the d i g behind a dozer. i i ) Crane from a l l e y s . Gantry crane t o run on r a i l s on top of p i l e s . Concrete Pumping i ) boom pump i i ) s l i c k l i n e and pump i i i ) s l i c k l i n e t o a p o r t a b l e boom - 157 -6.2.2 Model the A c t i v i t y The model of the " c o n s t r u c t r o o f " a c t i v i t y i s q u i t e simple. The a c t i v i t y must f o l l o w the w a l l s f o r s t r u c t u r a l support reasons. The a c t i v i t y must f o l l o w the p r e v i o u s r o o f segment f o r access and c o n t i n u i t y reasons. The l o g i c f o r both these precedence r e l a t i o n s h i p s i s f i n i s h - s t a r t . As has been mentioned under t a r g e t d u r a t i o n (6.1.7 above), the r o o f c o n s t r u c t i o n a c t i v i t y has the l o n g e s t d u r a t i o n and i s on the c r i t i c a l path f o r the e n t i r e l e n g t h of time i s takes t o c o n s t r u c t i t . T h e r e f o r e i t should be r e c o g n i z e d e a r l y - o n t h a t a p l a n f o r r o o f c o n s t r u c t i o n t h a t minimizes time d u r a t i o n w i l l be r e q u i r e d . One o p t i o n a v a i l a b l e t o minimize d u r a t i o n i s t o c o n s t r u c t m u l t i p l e t u n n e l segments d u r i n g each pour. T h i s has advantages i n t h a t the time r e q u i r e d t o cure the c o n c r e t e p r i o r t o s t r i p p i n g w i l l be c u t i n h a l f . Another advantage i s the r e d u c t i o n i n the number of bulkheads r e q u i r e d . The t r a d e o f f w i l l be i n the added expense of r e n t i n g or p u r c h a s i n g more form c a p a c i t y . - 158 -F o r t h e t e s t e x a m p l e , t h e m o d e l o f t h e r o o f a c t i v i t y i n t e r m s o f i t s o p e r a t i o n s a p p e a r s i n p r e l i m i n a r y b a r c h a r t f o r m a s f o l l o w s : A s s e m b l e t o w e r s P l a c e t o w e r s E r e c t b e a m s E r e c t p l a t e g i r d e r s F r e e f o r m b e t w e e n p a n e l s O r d e r a n d c r a n e r e b a r t o p o s i t i o n P l a c e r e b a r F o r m b u l k h e a d P o u r c o n c r e t e C u r e S t r i p f o r m s F i g u r e 39 P r e l i m i n a r y B a r c h a r t f o r A c t i v i t y " R o o f " I n t h e t e s t c a s e a s d e s c r i b e d a b o v e , t h e f i r s t f o u r o p e r a t i o n s w o u l d b e d o n e o n c e a n d t h e r e a f t e r t h e t o w e r - b e a m - p l a t e a s s e m b l y w o u l d b e w h e e l e d t o t h e n e x t l o c a t i o n a h e a d . I n t h i s e x a m p l e , t h e o p e r a t i o n s a n d s e q u e n c i n g a r e k n o w n b u t t h e d u r a t i o n s a r e n o t . 6 . 2 . 3 C o n t i n u o u s o r L i n e a r C r e w S c h e d u l i n g ? B e c a u s e o f t h e c u r i n g t i m e o f u p t o 4 d a y s , a n d t h e f i n i s h - s t a r t r e l a t i o n s h i p t o t h e n e x t r o o f s e g m e n t , t h e c r e w s c a n n o t b e s c h e d u l e d c o n t i n u o u s l y f o r a g i v e n a c t i v i t y . A f i l l e r p r o j e c t i s r e q u i r e d f o r t h e d u r a t i o n o f t h e c u r e . O n e o p t i o n w o u l d b e t o - 159 -schedule " w a l l " o p e r a t i o n s and " r o o f " o p e r a t i o n s i n a continuous manner. Were t h i s o p t i o n t o d o v e t a i l c l e a n l y , the m u l t i - a c t i v i t y continuous s c h e d u l i n g format would be a p p l i c a b l e . I t would appear as f o l l o w s : Days 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 C C P o s i t i o n r o o f form assembly C — C Freeform between panels I M a t e r i a l h a n d l i n g , rebar I 1 P l a c e rebar Roof C C Form bulkhead L Pour concr e t e * * Cure r o o f L — L S t r i p r o o f forms I 1 Rebar w a l l s Leaend C C P o s i t i o n w a l l form Wall C — C Form w a l l bulkhead C = Carpenters CC I n s t a l l t i e rods I = Ironworkers L Pour c o n c r e t e L = Laborers ** Cure L-L S t r i p C C P o s i t i o n next r o o f e t c F i g u r e 40 M u l t i - a c t i v i t y Crew Sch e d u l i n g f o r "Wall" and  "Roof" A c t i v i t i e s . In the case l a i d out here, the forming crew i s almost working c o n t i n u o u s l y between the two a c t i v i t i e s . The r e b a r crew e x h i b i t s g r e a t e r c o n t i n u i t y but s t i l l l e s s than 100% u t i l i z a t i o n . The above p l a n n i n g o p t i o n i s a good s t a r t on the p l a n n i n g of the r o o f and w a l l a c t i v i t i e s . And i n keeping with the s t a t e d theory, the rough s c h e d u l i n g has o c c u r r e d p r i o r t o the a c t u a l d e s i g n of - 160 -how the a c t i v i t y i s t o be c o n s t r u c t e d . An estimate of d u r a t i o n f o r the crew o p e r a t i o n s has been added t o see i f the continuous crew s c h e d u l i n g i s f e a s i b l e . The l a s t item from the General P l a n n i n g Model, a c t i v i t y l e v e l , i s to s o r t the o p e r a t i o n s by impact t o the a c t i v i t y as a whole, g r e a t e s t impact f i r s t . The shore-tower assemblies have the g r e a t e s t impact on the speed of the a c t i v i t y . T h e r e f o r e t h a t a c t i v i t y w i l l be examined f i r s t . 6.3 O p e r a t i o n L e v e l T e s t i n g F i r s t o p e r a t i o n : Shore and form r o o f . 6.3.1 Create O p e r a t i o n Worksheet At t h i s p o i n t we want t o l i s t f e a s i b l e o p t i o n s and c o n t r a s t t h e i r methods, c o s t s , and d u r a t i o n s . The f o l l o w i n g f i g u r e p r o v i d e s the framework. - 161 -D e s c r i p t o r Method Du r a t i o n per u n i t U n i t Cost Opi 1 2 3 ;ion Rented l i g h t towers, a l u m a j o i s t , plywood E f c o 50 k i p towers, header beams, p l a t e girde] Owned 100 k i p towers, 12" beams, p l a t e g i r d e r s rs 5 days 2 days 7 days $ 1000 2000 1500 Note: U n i t s r e f e r t o u n i t a c t i v i t i e s , 50' segments. F i g u r e 41 Spreadsheet of x O p t i o n s Versus D e s c r i p t o r s ' f o r  Operation "Shore and Form Roof". The v a l u e s f o r the o p t i o n s ( f i c t i t i o u s i n t h i s case) are d e r i v e d from s u p p l i e r s quotes, estimates of manhours, and p r e v i o u s experience t o develop p r e l i m i n a r y d u r a t i o n and c o s t e s t i m a t e s . Costs and d u r a t i o n s i n t h i s case i n c l u d e a l l of the s h o r i n g and forming o p e r a t i o n s i n c l u d i n g s t r i p p i n g . T h i s case i s i n t e r e s t i n g because we must now f i n d the v a l u e of the d i f f e r e n c e i n d u r a t i o n from a s u b - p r o j e c t s t a n d p o i n t . The t o t a l of the a d d i t i o n a l d u r a t i o n r e q u i r e d f o r #2 over #1 i s 12 segments times 3 days = 3 6 days. The e x t r a d u r a t i o n i s simply not a v a i l a b l e i n t h i s p r o j e c t . So f o r t h i s t e s t case, the p r e l i m i n a r y s o l u t i o n i s #2, E f c o Towers. - 162 -The s h o r i n g and forming system i s now ready f o r refinement. P r e l i m i n a r y shop drawings would be produced and s u p e r i n t e n d e n t s r e s p o n s i b l e f o r the " r o o f c o n s t r u c t i o n " would be i n c l u d e d i n d i s c u s s i o n s . 6.3.2 C a l c u l a t e Major Resource Requirements From 4.2.4. Step 5, the formula f o r determining the number of u n i t s of falsework r e q u i r e d i s : (NUA - 1) UAD Where: FU = # of Falsework U n i t s FU = NUA = # of U n i t A c t i v i t i e s (ATD - UAD) UAD = U n i t A c t i v i t y D u r a t i o n ATD = A c t i v i t y T a r g e t D u r a t i o n The assumption u n d e r l y i n g t h i s equation i s t h a t the falsework u n i t s are r e q u i r e d t o remain i n p l a c e u n t i l the l a s t o p e r a t i o n of a p a r t i c u l a r u n i t a c t i v i t y ( s t r i p p i n g ) i s f i n i s h e d . We do not as y e t know the u n i t a c t i v i t y d u r a t i o n . To estimate t h i s d u r a t i o n , a l l o p e r a t i o n d u r a t i o n s must be estimated and combined wi t h p o s s i b l e o v e r l a p p i n g t o get the p r e l i m i n a r y u n i t a c t i v i t y d u r a t i o n . The e f f e c t s of double or t r i p l e s h i f t s i s to be accomodated by the a c t i v i t y d u r a t i o n s estimated. The b a r c h a r t i n f i g u r e 40 w i l l p r o v i d e t h i s i n f o r m a t i o n when i t i s up-dated with o p e r a t i o n d u r a t i o n e s t i m a t e s . In t h i s case, the d u r a t i o n f o r the chosen method o p t i o n f o r s h o r i n g and forming the r o o f coencides w i t h the o r i g i n a l b a r c h a r t estimate. A l l o p e r a t i o n s have not y e t been designed, but i f we accept the b a r c h a r t as - 163 -c u r r e n t f o r the f i r s t i t e r a t i o n , the u n i t a c t i v i t y d u r a t i o n i s seen t o be 10 days. Note t h a t a l a t e r i t e r a t i o n of the combine " r o o f " and " w a l l " b a r c h a r t w i l l be r e q u i r e d i f i t i s s t i l l f e a s i b l e t o share crews between the r o o f and the w a l l s . From 6.1.7 the A c t i v i t y Target D u r a t i o n (ATD) i s shown t o be 13 weeks or 65 days at 5 days per week. The Number of U n i t A c t i v i t i e s (NUA) i s g i v e n as 12. And from above, the U n i t A c t i v i t y D u r a t i o n (UAD) i s 10 days. (NUA - 1) UAD (12 - 1) 10 FU = = = 2 Formwork U n i t s (ATD - UAD) (65 - 10) I f t h i s were the f i n a l c a l c u l a t i o n , we would need 2 segments (100 f e e t ) of r o o f forms. Let us see i f t h i s can be improved upon. Try two 50 f o o t segments p l a c e d and poured at one time. Days 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 C C P o s i t i o n r o o f form assembly C -C Freeform between panels I I M a t e r i a l h a n d l i n g , rebar I - I P l a c e rebar C C Form bulkhead Leaend LL Pour concr e t e C = Carpenters * * Cure r o o f I = Ironworkers L L S t r i p L = Laborers C->Next r o o f F i g u r e 42 Barchart Showing the E f f e c t of Doing Two Segments of  the Roof A c t i v i t y (100') a t One Time. - 164 -Fi g u r e 42 was modelled by d o u b l i n g the d u r a t i o n s of a l l o p e r a t i o n s except "Form bulkhead" and "Cure" which remained the same. So two segments are completed i n l e s s than twice the time. L e t ' s see what e f f e c t t h i s has on the formwork requirements. (6 - 1) 15 FU = = 1.5 Form u n i t s (65 - 15) The 100' segment o p t i o n r e q u i r e s l e s s t h a t two u n i t s o f falsework which i s an improvement. We are not a b l e t o reduce the falsework requirement below two u n i t s but we now have some f l o a t i n the schedule. We have now e s t a b l i s h e d the u n i t a c t i v i t y t a r g e t d u r a t i o n . In the process we have had to s p e c i f y the d u r a t i o n s o f the o p e r a t i o n s . The p l a n n i n g model w i l l d i r e c t the d e s i g n process i n t u r n t o these o p e r a t i o n s and we w i l l e i t h e r : 1. V e r i f y t h a t the d u r a t i o n s estimated here are f e a s i b l e . or 2. Return t o t h i s sheet f o r another i t e r a t i o n . 6.3.3 O p e r a t i o n Design Parameters The d e s i g n parameters f o r "shore and form r o o f " are l a r g e l y the same as those developed i n s e c t i o n 4.3.3 f o r b r i d g e beam c o n s t r u c t i o n . The spreadsheet of shore o p e r a t i o n s versus design - 165 -parameters w i l l p r o v i d e the same c h e c k l i s t of d e c i s i o n v a r i a b l e s as i n the de s i g n of the b r i d g e beam. A d d i t i o n a l r e p e t i t i o u s d e t a i l i s not r e q u i r e d here. Likewise the c o s t i n g process i s not e l a b o r a t e d on here as i t i s much the same as d e s c r i b e d i n the p l a n n i n g model, Chapter 4, s e c t i o n 4.3.4. In ge n e r a l one would analyse the c o s t s o f the f e a s i b l e o p t i o n s and h i g h l i g h t those o p t i o n s t h a t are most c o s t e f f e c t i v e . The process of o p e r a t i o n design i s i t e r a t i v e i n t h a t no o p e r a t i o n can be s p e c i f i e d w i t h complete c e r t a i n t y u n t i l a l l the o p e r a t i o n s t h a t comprise an a c t i v i t y are analysed and methods determined. T h e r e f o r e the l i s t of o p e r a t i o n s i s s y s t e m a t i c a l l y processed u n t i l we have a s o l u t i o n f o r each t h a t f i t s i n w i t h the oth e r o p e r a t i o n s of the a c t i v i t y . We have now e s t a b l i s h e d t h a t the d u r a t i o n s estimated f o r the v a r i o u s o p e r a t i o n s o f the a c t i v i t y " r o o f " are f e a s i b l e , have e s t a b l i s h e d methods, d r a f t e d p r e l i m i n a r y shop drawings, and c a l c u l a t e d c o s t estimates f o r the o p t i o n s of the o p e r a t i o n s i n q u e s t i o n . The o p e r a t i o n l e v e l i s n e a r l y complete. 6 . 3 . 6 C a l c u l a t e Crew S i z e R e f e r r i n g t o s e c t i o n 4.3.6 i n Chapter 4, we are g i v e n a method of e s t a b l i s h i n g a crew s i z e i f the c y c l e d u r a t i o n i s s p e c i f i e d - 166 -e a r l i e r . The crew c y c l e was not s p e c i f i e d i n the a c t i v i t y l i n e a r s c h e d u l i n g s e c t i o n 6.2.3, because the crews were not c o n t i n u o u s l y engaged i n work on these o p e r a t i o n s . Now i s the time t o i n v e s t i g a t e m u l t i - a c t i v i t y crew s c h e d u l i n g between the a c t i v i t i e s " w a l l s " and " r o o f " . The " w a l l s " a c t i v i t y w i l l have a l r e a d y undergone an a n a l y s i s s i m i l a r t o the " r o o f " a c t i v i t y . The methods, d u r a t i o n estimates, c o s t e s t i m a t e s , and p r e l i m i n a r y drawings are completed. L e t s compare the b a r c h a r t s of the two a c t i v i t i e s t o see i f they are a t a l l compatible f o r crew s h a r i n g . - 167 -Days 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 c C P o s i t i o n r o o f form assembly C— C Freeform between panels I I M a t e r i a l h a n d l i n g , rebar I I P l a c e rebar Roofs C C Form bulkhead 1 & 2 LL Pour c o n c r e t e * * Cure r o o f L L S t r i p C->Next r o o f — — I -I Rebar w a l l s C P o s i t i o n w a l l form Wall 3 C-C Form w a l l bulkhead C-C I n s t a l l t i e rods L Pour c o n c r e t e *-* Cure — L-L S t r i p Rebar Walls I 1 — P o s i t i o n w a l l form C LEGEND Form w a l l bulkhead C-C Wall 4 C = Carpenters I n s t a l l t i e rods C-C I = Ironworkers Pour concr e t e L L = Laborers Cure *-* S t r i p L-L —> F i g u r e 43 B a r c h a r t Showing M u l t i - a c t i v i t y Continuous Crew  Scheduling. I t can be seen from the above b a r c h a r t t h a t the forming o p e r a t i o n s can be p o s i t i o n e d so t h a t they do not o v e r l a p between the two a c t i v i t i e s . The same i s t r u e f o r the rebar p l a c i n g o p e r a t i o n . So the concept of m u l t i - a c t i v i t y , continuous crew s c h e d u l i n g appears to work with the above s c e n a r i o . The next step would be t o a s s i g n manpower to the crews so t h a t the manpower r e q u i r e d matches the manpower a v a i l a b l e . - 168 -These are h y p o t h e t i c a l a c t i v i t i e s but they demonstrate how crews can be j u g g l e d on paper between a c t i v i t i e s t o take advantage of c o n t i n u i t y of crew sequencing while s t i l l d e l i v e r i n g the same p r o d u c t i o n r a t e . T h i s example does not show a l l of the d e c i s i o n s v a r i a b l e s t h a t are p r e s e n t . Another case i t might have n e c e s s i t a t e d the c h o i c e of a d i f f e r e n t forming system t h a t would b e t t e r u t i l i z e the crews a v a i l a b l e . The same technique can be a p p l i e d t o equipment useage. E s s e n t i a l l y , a v a i l a b i l i t y of equipment must be compared and f i t t e d t o the equipment requirement. 6.4 T e s t i n g t h e Model: R e s u l t s I t seem f a i r t o say t h a t the model c o n s t r u c t e d f o r the Bridge P r o j e c t performed reasonably w e l l f o r a n a l y s i s of the p l a n n i n g elements a s s o c i a t e d w i t h Cut and Cover Tunnel C o n s t r u c t i o n . F l e x i b i l i t y i s c e r t a i n l y a very important element i n the framework of a model or a computer system t h a t uses the model. The concepts were l a r g e l y unchanged from Bridge t o Tunnel but the a p p l i c a t i o n of the concepts d i d change and the proceedures were not i d e n t i c a l . - 169 -C H A P T E R 7 C O N C L U S I O N S 7 . 1 A c c o m p l i s h m e n t s T h i s t h e s i s b e g a n b y i d e n t i f y i n g c o n s t r u c t i o n i n f o r m a t i o n s y s t e m s a s a n a r e a o f o n - g o i n g d e v e l o p m e n t i n t h e c o n s t r u c t i o n i n d u s t r y . O f p a r t i c u l a r i n t e r e s t t o t h i s w o r k i s t h e c o n c e p t o f a c t i v i t y p l a n n i n g . W h a t i s r e q u i r e d t o d e s i g n a n d p l a n a n a c t i v i t y ? W h a t t h e o r i e s a r e u s e f u l t o d e v e l o p a p r o t o c o l f o r t h e e s t a b l i s h m e n t o f a c t i v i t y d e s i g n ? A n d w h a t t o o l s a r e u s e f u l t o w a r d s t h a t e n d ? C h a p t e r 3 a s s e m b l e s a t a b l e o f f u n c t i o n s a n d e n v i r o n m e n t s f o r t h e e x e c u t i o n o f t h e s e f u n c t i o n s . I t c o n c l u d e s t h a t t w o c o m p u t e r e n v i r o n m e n t s , D a t a b a s e a n d S c h e d u l e r , a r e a b l e t o e f f i c i e n t l y p e r f o r m t h e r e q u i r e d a c t i v i t y p l a n n i n g f u n c t i o n s . T h i s r e s e a r c h p r o p o s e s t o o p e r a t e t h e s e t w o e n v i r o n m e n t s i n t a n d e m a s i n d i v i d u a l m o d u l e s o f a n o v e r a l l i n f o r m a t i o n s y s t e m . I n C h a p t e r 4 , t h i s t h e s i s d e v e l o p s a s p e c i f i c a t i o n f o r a " G e n e r a l P l a n n i n g M o d e l f o r C o n c r e t e C o n s t r u c t i o n " t h a t w i l l u t i l i z e a p r o g r a m a b l e d a t a b a s e a s a n o p e r a t i n g e n v i r o n m e n t . T h e p l a n n i n g m o d e l t h e n b e c o m e s t h e d r i v e r o f t h e a c t i v i t y p l a n n i n g p r o c e s s . T h e p l a n n i n g m o d e l a n d e s t a b l i s h e s a s t r u c t u r e t o a c c o m o d a t e t h e m y r i a d o f d e t a i l s c o m m o n t o c o n c r e t e c o n s t r u c t i o n . T h r e e l e v e l s o f h i e r a r c h y a r e u t i l i z e d e x t e n s i v e l y ( P r o j e c t , A c t i v i t y , a n d O p e r a t i o n ) w h i l e f o u r o t h e r l e v e l s ( L o c a t i o n , R e s o u r c e , D e s c r i p t o r , a n d P h a s e ) r o u n d o u t t h e c a p a b i l i t y o f t h e d a t a c o l l e c t i o n a n d a n a l y s i s s y s t e m . - 170 -F r o m t h e p r o j e c t l e v e l o f t h e p l a n n i n g h i e r a r c h y c o m e s t h e d e v e l o p m e n t o f a s c h e d u l i n g t e c h n i q u e c a l l e d " t a r g e t a c t i v i t y d u r a t i o n a l l o c a t i o n " . T h i s m e t h o d d i s t r i b u t e s t h e m i l e s t o n e d u r a t i o n a m o n g s t a c t i v i t i e s b y a r a t i o n a l a p p r o a c h a n d p r o v i d e s a f e a s i b l e t a r g e t d u r a t i o n f o r t h e p l a n n e r t o a i m a t w h i l e d e s i g n i n g t h e a c t i v i t y . A f i n d i n g f r o m t h e A c t i v i t y L e v e l o f t h e h i e r a r c h y i s a m e t h o d o f d e v e l o p i n g c o n t i n u o u s c r e w s c h e d u l e s f o r o p e r a t i o n s i n v o l v e d i n r e p e t i t i v e a c t i v i t i e s . A s w e l l , v a r i o u s c o m m o n l y k n o w n s c h e d u l i n g m e t h o d s a r e s p e c i f i e d i n t h e p l a n n i n g m o d e l f o r u s e a t a p p r o p r i a t e t i m e s . A m a j o r s e c t i o n o f t h e O p e r a t i o n L e v e l h i e r a r c h y i s d e v o t e d t o t h e c a l c u l a t i o n o f o p t i m a l f o r m w o r k a n d s h o r i n g h a r d w a r e r e q u i r e m e n t s b a s e d o n t h e c o n t i n u o u s c r e w s c h e d u l e s p r e v i o u s l y d e r i v e d . A n o t h e r o u t c o m e o f t h i s l e v e l o f a n a l y s i s i s a c h e c k l i s t o f d e c i s i o n v a r i a b l e s t h a t c a n b e b r o u g h t t o p l a y o n t h e c o n c r e t e c o n s t r u c t i o n o p e r a t i o n s o f f o r m w o r k , c o n c r e t e p l a c e m e n t , a n d r e b a r p l a c e m e n t . M a n i p u l a t i o n o f t h e s e d e c i s i o n v a r i a b l e s w i t h i n t h e p l a n n i n g m o d e l i s t h e e s s e n c e o f a c t i v i t y o r o p e r a t i o n d e s i g n a s l a i d o u t b y t h i s t h e s i s . F i n a l l y , c r e w s i z e c a l c u l a t i o n a n d e q u i p m e n t a l l o c a t i o n a r e d i s c u s s e d a n d a l g e b r a i c a n d g r a p h i c a l m e t h o d s a r e e m p l o y e d t o a l l o c a t e t h e s e r e s o u r c e s . C h a p t e r 5 p r e s e n t s t h e r e s u l t s o f i n f o r m a t i o n s y s t e m f i l e o r g a n i z a t i o n g i v e n t h e f u n c t i o n s o f C h a p t e r 4 . T w o t y p e s o f d a t a s t r u c t u r e s a r e i l l u s t r a t e d , r e l a t i o n a l d a t a b a s e f i l e s a n d - 171 -multidimensional spreadsheet f i l e s . From the layout of the records and f i e l d s within these environments, one gets a f e e l for the quantity of data to be c o l l e c t e d and u t i l i z e d by the system. Chapter 6 serves to v e r i f y that the planning model, as presented i n Chapter 4 , w i l l be viable i n other concrete construction applications. Whereas Chapter 4 provided examples from a concrete bridge project, Chapter 6 uses a cut and cover tunnel project to compare the p o r t a b i l i t y and f l e x i b i l i t y of the planning model. One major finding from schedule analysis of the tunnel i s the need to be able to sequence a c t i v i t i e s i n a sub-project on a continuous basis. This finding allows the planning model to accomodate the sequencing needs of cut and cover a c t i v i t i e s as discovered i n the Seattle Subway case study. This example i l l u s t r a t e d the additional c a p a b i l i t i e s required of the general planning model i n order to better model r e a l i t y . The f i n a l finding from chapter 6 i s that the "General Planning Model for Concrete Construction" i s quite f l e x i b l e and transportable. The model when applied to a cut and cover tunnel was e a s i l y molded to the planning tasks at hand. In fact, the actual planning processes proved to be very s i m i l a r to those of a concrete bridge project. - 172 -7.2 Recommendations f o r Future Research T h i s t h e s i s developed a framework from which t o monitor and p l a n c o n s t r u c t i o n a c t i v i t i e s and o p e r a t i o n s . One t a s k not addressed i s a method of d i s c e r n i n g the p r o d u c t i v i t y v a l u e s of the many d e c i s i o n v a r i a b l e s t h a t comprise an o p e r a t i o n . R e g r e s s i o n a n a l y s i s i s a p o s s i b i l i t y t h a t may y i e l d r e s u l t s . D e c i s i o n v a r i a b l e p r o d u c t i v i t y a n a l y s i s i s a t a s k f o r f u t u r e r e s e a r c h . The combination of database and CPM s c h e d u l i n g c a p a b i l i t i e s w i t h i n the same program i s a c a p a b i l i t y not seen i n the l i t e r a t u r e and software search undertaken f o r t h i s t h e s i s . There would be b e n e f i t s as w e l l as a d d i t i o n a l c o m p l i c a t i o n t o such a combination. I t would seem to be an area w e l l s u i t e d to f u t u r e r e s e a r c h . Another area t h a t beckons a d d i t i o n a l r e s e a r c h i s the s u b j e c t d i s c u s s e d b r i e f l y i n Chapter 2, s e c t i o n 2.2.2, o p t i m i z a t i o n by means of a l i n e a r programing pro c e s s . The authors of the reviewed a r t i c l e accomplished o p t i m i z a t i o n u s i n g l i n e a r programming f o r an earth-moving c o n s t r u c t i o n p r o j e c t . The r e l e v a n c e of t h a t technique to co n c r e t e c o n s t r u c t i o n i s an area sugested f o r f u t u r e r e s e a r c h . - 173 -REFERENCES 1. Anderson, Thomas R., " C o n s t r u c t i o n Management Software Requirements", Small Computers i n C o n s t r u c t i o n , Proceedings of a Symposium, ASCE C o n s t r u c t i o n D i v i s i o n , A t l a n t a , Georgia. May, 1984. 2. Baldwin, A. N., and McCaffer, R., "The Implementation of Computer-aided E s t i m a t i n g Systems i n C o n s t r u c t i o n Companies", I n s t n C i v . Engrs, P a r t 1, 1984, 76, February, p 237 - 248. 3. C l a r k , F o r r e s t D., "Labor P r o d u c t i v i t y And Manpower F o r e c a s t i n g " , T r a n s a c t i o n s of the AACE. 2 9th annual  meeting of the American A s s o c i a t i o n of Cost Engineers, Denver, Colorado, 1985. 4. Dabbas, M.A.A., and H a l p i n , D.W., " I n t e g r a t e d P r o j e c t and Process Management", J o u r n a l of the C o n s t r u c t i o n D i v i s i o n , ASCE, V o l . 108, No. C03, September, 1982. 5. H a l p i n , D.W., and Woodhead, R.W., Design of C o n s t r u c t i o n  and Process Operations. John Wiley, New York, NY., 1976. 6. Herbsman, Zohar, and M i t r a n i , J.D., "INES—An I n t e r a c t i v e E s t i m a t i n g System", J o u r n a l o f C o n s t r u c t i o n E n g i n e e r i n g and  Management. V o l . 110, No. 1, March, 1984. 7. K i r b y , Robert C., and K a l i n k a , David A., "Microcomputer Based Cost C o n t r o l System", T r a n s a c t i o n s o f the American  a s s o c i a t i o n o f Cost Engineers. 1985. 8. Law, Gordon Ki-wai, D e c i s i o n Support System f o r  C o n s t r u c t i o n C y c l e Design. T h e s i s f o r the degree of Master of A p p l i e d Science, Graduate S t u d i e s , Department of C i v i l E n g i n e e r i n g , U n i v e r s i t y of B r i t i s h Columbia, A p r i l , 1987. 9. Lo, Simon, P r o j e c t Management Information System For Small  C o n t r a c t o r s For Housing P r o j e c t s , T h e s i s , Centre f o r B u i l d i n g S t u d i e s , F a c u l t y of E n g i n e e r i n g , Concordia U n i v e r s i t y , J u l y , 1984. 10. McGartland, M a r t i n R., and Hendrickson, C. T., "Expert Systems f o r C o n s t r u c t i o n P r o j e c t M o n i t o r i n g " , J o u r n a l of  C o n s t r u c t i o n E n g i n e e r i n g and Management. V o l . I l l , No. 3, September, 1985. 11. Means, R. S. Company Inc., "Winter C a t e l o g " 100 C o n s t r u c t i o n P l a z a , Kingston, Massachusetts 02364, 1987. - 174 -12. Muel ler , Freder ick W., and Muel ler , P h i l l i p F . , "Integrated Computer Systems", Transactions of the 28th annual meeting  of the American Assoc iat ion of Cost Engineers, 1984. 13. Postula , Frank D . , "Development of an Integrated Cost Forecast ing System", Transactions of the American  Assoc ia t ion of Cost Engineers, 1985. 14. Revay, Stephen G, "Improved Product iv i ty Through Integrat ing Work Instruct ions With Progress Contro l" , AACE, 1978. 15. Rounds, J . L . , "The E l e c t r o n i c Spreadsheet: A S i m p l i f i e d Approach to Computer-assisted Construct ion Est imating", Cost  Engineering, V o l . 26, No. 6, December 1984. 16. R u s s e l l , A. D . , "Microcomputers, Management, and H i g h - r i s e Construct ion: The Next Step", Canadian Journal Of C i v i l  Engineering. 12, 396-414, 1985. 17. Stapelberg, L . S . , "Construction Planning and Contro l : Current Pract ice and Continuing Challenges", Symposium on  Computers i n Construct ion, CSIR Conference Centre, South A f r i c a , September, 1982. 18. Tokunaga, Nobuaki, and Yoshide, Tetsuo, "Construction Planning and Scheduling System for C i v i l Engineering Works", Technical Review. V o l . 21 (2), June, 1984. 19. Wexler, Stephen C . , "Cost Containment and Cost Reduction", Transactions of the American Assoc ia t ion of Cost Engineers. 1985. - 175 -« INFORMATION SYSTEM MENU OF SYSTEM FUNCTIONS MENU MAIN SUB SCREEN MENU MENUS TEXT 0 EXIT PROGRAM M 1 TIME AND COST CONTROL MODULES 1.0 E x i t T 1.1 I n t r o d u c t i o n M 1.2 Data Entry; .0 E x i t S .1 Tine sheets S .2 Purchase or d e r s .3 Invoices S .4 Company i n v e n t o r y draw requests .5 Company i n v e n t o r y d e l i v e r i e s S .6 I n d i r e c t c o s t input . 7* Reports M 1.3 Cost Control Monitoring .0 £xit S .1 View WBS h i e r a r c h y by rec o r d name S .2 S e l e c t s o r t mode (by trade or by structure) .3 S e l e c t r e c o r d s / f i e l d s f o r data e d i t i n g S .4 Analyze c o s t s S .5 Summarize c o s t s S 1.4 F o r e c a s t i n g p r o j e c t c o s t s S 1.5 Monthly payment data s t r u c t u r e .0 E x i t .1 General c o n t r a c t o r .2 Sub—contractors 1.6 Company a r c h i v e s a-f p r o j e c t summaries ESTIMATING AND PLANNING MODULE: M 2. PROJECT LEVEL DEFINITION 2.0 E x i t 2.1 S e l e c t p r o j e c t M 2.2 D e f i n i t i o n input: .0 E x i t S .1 P r o j e c t - 176 -.2 A c t i v i t i e s .3 Operations . 4 Q i n t Divisions .3 L o c a t i o n s M 2.3 Work breakdown s t r u c t u r e .0 E x i t S .1 Browse -For s u i t a b l e p r o t o t y p e .2 Copy p r o t o t y p e .3 Modify .4 Add " C l i e n t D i v i s i o n s " .5 Add l o c a t i o n s .6 Report M 2-4 F i e l d s t r u c t u r e ( p r o j e c t , a c t i v i t y , o p e r a t i o n ) : .0 E x i t S .1 Drowse -For s u i t a b l e p r o t o t y p e .2 Copy p r o t o t y p e .3 Modi-fy .4 Report M 2.S Q u a n t i t y s u r v e y : .0 E x i t S .1 E x p o r t WBS t o spreadsheet S .2 I a p o r t q u a n t i t y s u r v e y f r o e spread sheet S 2.6 O u t l i n e erf s c h e d u l i n g program -functions 2.7 Schedule: t a r g e t a c t i v i t y d u r a t i o n c a l c u l a t i o n s tt 3. ACTIVITY LEVEL DEFINITION 3-0 E x i t 3.1 S e l e c t a c t i v i t y M 3.2 A c t i v i t y d e f i n i t i o n : .0 E x i t S .1 P r o j code .2 A c t i v i t y code .3 A c t i v i t y n u t .4 A c t i v i t y d e s c r i p t i o n .5 C o n d i t i o n s .6 T i n e c o n s t r a i n t s .7 P h y s i c a l c o n s t r a i n t s .8 Methods tt 3.3 A c t i v i t y work breakdown s t r u c t u r e : .0 E x i t S .1 Browse f o r p r o t o t y p e : a c t ' y s w i t h nested oper'ns .2 Copy p r o t o t y p e .3 Modify (add o r e d i t o p e r a t i o n s , e tc) .4 Add " C l i e n t D i v i s i o n s " .3 Add l o c a t i o n s .6 Report - 177 -3.4 Sort, database far operation options and display 3.5 User* defined options 3.6 Summarize activity plan. (decision tree- shown) REPETITION PARAMETERS 4.0 Exit 4.1 Repetitious and continuous crew scheduling. 4.2 Standard crew cycle duration: calc 4.3 Unit activity cycle duration: calc 4.4 Test feasibility of standard crew cycle duration PRELIMINARY ACTIVITY SCHEDULES 5.0 Exit 5.1 Outline functions executed: i n scheduling program 5.2 Reports 5.3 NetMork 5.4 Bar chart 5.5 Line of balance graph ACTIVITY LEVEL COST PLANS? 6.0 Exit 6.1 Develop cost plans at activity level? If no go to 6.2 Edit activity records to include feasible options 6.3 Calculate cost per unit for each feasible option . 1 Labor .2 Materials .3 Equi paent .4 Sub—contracators 6.4 Choose minimum cost option. L i s t methods 6.5 Calculate crew size 6.6 Check assumptions of productivity Mith crew size 6.7 Repeat for a l l "no operation" activities OPERATION LEVEL COST PLANS 7.0 Exit 7.1 Select operation 7.2 Edit option records to include feasible options 7.3 Calculate controlling resource requirements ie. falsework 7.4 Obtain design input (ie beam and form sizing) 7.5 Calculate cost for each feasible option based on: .1 Labor . 2 Mater i al .3 Equipment .4 Sub—contracators 7.6 Choose minimum cost option. List methods 7.7 Calculate crew size based on productivity duration - 178 -7.8 Chock a s s u m p t i o n s : - p r o d u c t i v i t y v e r s u s crew s i z e 7.9 R e p e a t -for a l l o p e r a t i o n s o-f t h e a c t i v i t y 8. ACTIVITY SUMMARY 8.0 E x i t 8.1 A c t i v i t y l e v e l s c h e d u l i n g 8.2 C o a p i l e h i s t o g r a n o f e q u i p e e n t h o u r s 8.3 L e v e l e q u i p e e n t r e s o u r c e u s e a g e 8.4 Update s c h e d u l e s . 8.5 Check t a r g e t v e r s u s p l a n d u r a t i o n 8.6 A n a l y s e r e s u l t i n g a c t i v i t y p l a n . A l t e r n a t i v e s ? 8.7 R e p e a t f o r a l l a c t i v i t i e s 9. PROJECT SCHEDULING 9.0 E x i t 9.1 P r o j e c t l e v e l s c h e d u l i n g 9.2 Network 9.3 B a r c h a r t 9.4 Per 11 t e c h n i q u e 9.5 L i n e o f b a l a n c e a n a l y s i s 9.6 C o n t r a c t v . s c h e d u l e d u r a t i o n ? C r a s h i n g r e q u i r e d ? 1 0 . RESOURCE LEVELLING 10.0 E x i t 10.1 C o a p i l e r e s o u r c e h i s t o g r a m s -for p r o j e c t s 10.2 Cash f l o w 10.3 F i n a n c i a l a n a l y s i s 10.4 Manpower 10.3 E q u i p e e n t 10.6 L e v e l p r o j e c t r e s o u r c e s 1 1 . TENDER SUBMITTAL OR COST UP—DATE 11.0 E x i t 11.1 S u b — t o t a l s o-f c o s t s : 11.2 Overhead, p r o f i t , and c o n t i n g e n c i e s 11.3 D i s t r i b u t e t o t a l s among pay d i v i s i o n s 11.4 C a l c u l a t e u n i t r a t e s f o r t e n d e r 11.5 T e n d e r s u b a i t t e d 

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