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Comparison of creep/duration of load performance in bending of Parallam® parallel strand lumber to machine… Craig, Bruce A. 1986

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COMPARISON OF CREEP/DURATION OF LOAD PERFORMANCE IN BENDING OF PARALLAM* PARALLEL STRAND LUMBER TO MACHINE STRESS RATED LUMBER by BRUCE A. CRAIG B. Sc. i n Chemical Physics Simon Fraser U n i v e r s i t y , 1976 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n The Department of Forestry 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. 5/ The University of B r i t i s h Columbia December 1986 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 F o r e s t r y  The University of British Columbia 1956 Main Mall Vancouver, Canada V6T 1Y3 Date December 16,1986 ABSTRACT A comparison of the creep/duration of load (DOL) performance of a new str u c t u r a l wood composite material c a l l e d Parallam® p a r a l l e l strand lumber (PSL) to two grades of machine-stress-rated (HSR) Douglas-fir lumber i s presented i n t h i s thesis. Evaluation of the creep/DOL performance was made on nominal 2x4 members under constant bending stress at three stress l e v e l s . A t o t a l of 306 test specimens were evaluated for a 15-1/2 month time period. The analysis suggests that the duration of load e f f e c t for Parallam PSL was consistent with the Madison curve for the time period studied while the MSR Douglas-fir lumber was consistent with recent duration of load models developed for structural lumber. The analysis also indicates that the current duration of load adjustment factors can be applied to develop working stresses for Parallam. The creep behaviour of the Parallam PSL was found to be equivalent or better than the two MSR lumber grades under dry-service conditions. Furthermore, evidence of l i n e a r v i s c o e l a s t i c behaviour was found for a l l t e s t materials within the range of applied stresses eval uated. i v Two mathematical models of creep were f i t t e d t o the creep data and compared. A '4-parameter l i n e a r v i s c o e l a s t i c 1 model f i t t e d the creep data b e t t e r than an e m p i r i c a l 'power curve 1 model. The model parameters developed provide a b a s i s f o r e s t i m a t i n g the mean creep behaviour and v a r i a b i l i t y i n creep response f o r these m a t e r i a l s under i n - s e r v i c e l o a d c o n d i t i o n s f o r dry-s e r v i c e environments. V TABLE OF CONTENTS PAGE ABSTRACT i i i TABLE OF CONTENTS V L I S T OF TABLES v i i i L IST OF FIGURES X ACKNOWLEDGEMENTS xv CHAPTER 1.0 INTRODUCTION 1 1.1 Background 1 1.2 O b j e c t i v e s 5 1.3 T e s t D e s i g n 6 2.0 THEORY 8 2.1 Creep 8 2.1.1 Creep Terms 8 2.1.2 F a c t o r s A f f e c t i n g Creep 10 2.2 M a t h e m a t i c a l Models of Creep 12 2.2.1 E m p i r i c a l Curve F i t t i n g -Power Model 12 2.2.2 L i n e a r V i s c o e l a s t i c Model 13 3.0 EXPERIMENTAL 16 3.1 T e s t M a t e r i a l s 16 3.1.1 D o u g l a s - f i r 16 3.1.2 P a r a l l a m 16 v i 3.2 M a t e r i a l P r e p a r a t i o n 17 3.2.1 Sampling 17 3.2.2 C o n d i t i o n i n g 18 3.2.3 P o p u l a t i o n D i v i s i o n 18 3.3 Short Term F l e x u r e T e s t s 21 3.3.1 Te s t Method 21 3.3.2 Test Procedure 22 3.4 Long Term Creep/Rupture Study 23 3.4.1 Test C o n d i t i o n s 23 3.4.2 T e s t Method 23 3.4.3 Test Apparatus 24 3.4.4 T e s t Layout 25 3.4.5 Deformation Measurement 26 3.4.6 T e s t Procedure 26 4.0 ANALYSIS OF TEST RESULTS 2 8 4.1 Short Term Flexure R e s u l t s 28 4.2 Creep/Rupture Study 3 0 4.2.1 Test Environment 30 4.2.2. I n i t i a l Deformation and Modulus of E l a s t i c i t y 33 4.2.3 Creep (Deformation) Study R e s u l t s 34 4.2.4 Rupture ( F a i l u r e ) Study Re s u l t s 36 5.0 DISCUSSION AND TECHNICAL ANALYSIS 40 5.1 D u r a t i o n of Load (Rupture) R e s u l t s 40 vii... 5.1.1 Overview 40 5.1.2 A n a l y s i s Methods 42 5.1.3 S u r v i v a l P r o b a b i l i t i e s . . 43 5.1.4 A p p l i e d S t r e s s R a t i o Using C o n t r o l Samples... 46 5.1.5 A p p l i e d S t r e s s R a t i o Using Test Data 47 5.1.6 D i s c u s s i o n 49 5.1.7 Summary.... 50 5.2 Creep R e s u l t s 52 5.2.1 Creep D e f l e c t i o n 52 5.2.2 F r a c t i o n a l Creep 54 5.2.3 D i s c u s s i o n 58 5.2.4 Summary 60 6.0 MODELLING OF CREEP BEHAVIOUR 61 6.1 Power Curve Model 61 6.2 L i n e a r V i s c o e l a s t i c Model 63 6.3 D i s c u s s i o n and Summary 65 7.0 CONCLUSIONS 6 8 BIBLIOGRAPHY 7 0 APPENDICES 166 I S t a t i s t i c a l Analyses 167 II Shear-Free Modulus of E l a s t i c i t y R e s u l t s . . 171 I I I D e f l e c t i o n and F r a c t i o n a l Creep R e s u l t s . . . 175 v i i i TABLE 1 TABLE 2 TABLE 3A TABLE 3B TABLE 4A TABLE 4B TABLE 5 A TABLE 5B TABLE 5C TABLE 6 TABLE 7 A TABLE 7B TABLE 7C TABLE 8A TABLE 8B TABLE 8C TABLE 9A L I S T O F T A B L E S PAGE P o p u l a t i o n d i v i s i o n - Summary D o u g l a s - f i r MOE Values 149 Pop u l a t i o n D i v i s i o n - Summary Par a l l a m PSL MOE Values 150 Short Term Strength F l e x u r e R e s u l t s - M o i s t -ure Content At Tes t 151 Short Term Strength F l e x u r e R e s u l t s - M o i s t -ure Content A d j u s t e d t o 12% 151 Duration of Load S u r v i v o r s F l e x u r e R e s u l t s -Moisture Content At T e s t 152 Duration of Load S u r v i v o r s F l e x u r e R e s u l t s -Moisture Content A d j u s t e d t o 12% 152 Deformation/Rupture Data For S t r e s s L e v e l 1 153 Deformation/Rupture Data For S t r e s s L e v e l 2 154 Deformation/Rupture Data For S t r e s s L e v e l 3 155 Duration of Load Study - Time to F a i l u r e Data 156 Curve F i t Parameters - 1650F, 1.5E Douglas-f i r S t r e s s L e v e l 1 157 Curve F i t Parameters - 1650F, 1.5E Douglas-f i r S t r e s s L e v e l 2 158 Curve F i t Parameters - 1650F, 1.5E Douglas-f i r S t r e s s L e v e l 3 159 Curve F i t Parameters - 2400F, 2.0E Douglas-f i r S t r e s s L e v e l 1 160 Curve F i t Parameters - 2400F, 2.0E Douglas-f i r S t r e s s L e v e l 2 161 Curve F i t Parameters - 2400F, 2.0E Douglas-f i r S t r e s s L e v e l 3 162 Curve F i t Parameters - Parallam PSL - S t r e s s L e v e l 1 163 ix TABLE 9B Curve F i t Parameters - Parallam PSL - S t r e s s L e v e l 2 164 TABLE 9C Curve F i t Parameters - Parallam PSL - S t r e s s L e v e l 3 165 X LIST OF FIGURES PAGE F i g u r e 1 Parallam PSL shown i n nominal 2"x 2" to 4"x 12" c r o s s - s e c t i o n s 72 F i g u r e 2 Parallam PSL code r e p o r t 73 F i g u r e 3 R e l a t i o n of working s t r e s s to d u r a t i o n of l o a d 74 F i g u r e 4 Comparison of d u r a t i o n of l o a d r e s u l t s of 2" x 6" Hemlock lumber (No.2 & b e t t e r ) to the Madison Curve 75 F i g u r e 5 Creep behaviour a t a) s e l e c t e d l o a d l e v e l s b) c o r r e s p o n d i n g d e f l e c t i o n s and stages of creep c) creep r a t e 76 F i g u r e 6 F a c t o r s a f f e c t i n g creep (From N i e l s e n , 1972 ) 77 F i g u r e 7 Schematic diagram of D o u g l a s - f i r p o p u l a t i o n d i v i s i o n procedure 78 F i g u r e 8 Schematic diagram of Parallam PSL p o p u l a t i o n d i v i s i o n procedure 79 F i g u r e 9 Schematic diagram of F l e x u r e T e s t setup 80 F i g u r e 10 Schematic diagram of moment arm l o a d t e s t j i g 81 F i g u r e 11 Warehouse t e s t arrangement 82 F i g u r e 12 Short term s t r e n g t h r e s u l t s - 1650F, 1.5E, D o u g l a s - f i r , MOR 83 F i g u r e 13 Short term s t r e n g t h r e s u l t s - 1650F, 1.5E f D o u g l a s - f i r f MOE 84 F i g u r e 14 Short term s t r e n g t h r e s u l t s - 2400F, 2.0E, D o u g l a s - f i r f MOR 85 F i g u r e 15 Short term S t r e n g t h r e s u l t s - 2400F, 2.0E, D o u g l a s - f i r , MOE 86 F i g u r e 16 Short term f l e x u r e r e s u l t s - P a r a l l a m PSL MOR 87 x i PAGE Fig u r e 17 Short term f l e x u r e r e s u l t s - Parallam PSL, MOE 88 Fi g u r e 18 L i n e a r r e g r e s s i o n a n a l y s i s of short term s t r e n g t h r e s u l t s (MOR vs MOE) -1650F, 1.5E, D o u g l a s - f i r 89 F i g u r e 19 L i n e a r r e g r e s s i o n a n a l y s i s of s h o r t term s t r e n g t h r e s u l t s (MOR vs MOE)-1400F, 2.0E, D o u g l a s - f i r 90 Figu r e 20 L i n e a r r e g r e s s i o n a n a l y s i s of s h o r t term s t r e n g t h r e s u l t s (MOR vs MOE) Parallam PSL 91 Fi g u r e 21 Warehouse e q u i l i b r u m moisture content d u r i n g t e s t 92 Fi g u r e 22 Specimen moisture content changes i n t e s t warehouse 93 Fi g u r e 23 L i n e a r r e g r e s s i o n a n a l y s i s of s h e a r - f r e e modulus of e l a s t i c i t y (MOEt) and apparent modulus of e l a s t i c i y (MOEa) of t e s t groups 94 F i g u r e 24 Creep D e f l e c t i o n data - 1650F Douglas-f i r - s t r e s s l e v e l 1 (2060 p s i ) 95 Figu r e 25 Creep D e f l e c t i o n data - 2400F Douglas-f i r s t r e s s l e v e l 1 (3000 p s i ) 96 Figu r e 26 Creep D e f l e c t i o n data - Parallam PSL s t r e s s l e v e l 1 (4000 p s i ) 97 Fi g u r e 27 Creep D e f l e c t i o n data - 1650F Douglas-f i r s t r e s s l e v e l 2 (2325 p s i ) 98 Fi g u r e 28 Creep D e f l e c t i o n data - 2400F Douglas-f i r s t r e s s l e v e l 2 (3375 p s i ) 99 Figu r e 29 Creep D e f l e c t i o n data - Parallam PSL -s t r e s s l e v e l 2 (4500 p s i ) 100 Fi g u r e 30 Creep D e f l e c t i o n data - 1650F Douglas-f i r s t r e s s l e v e l 3 (2575 p s i ) 101 Fi g u r e 31 Creep D e f l e c t i o n data - 2400F Douglas-f i r s t r e s s l e v e l 3 (3750 p s i ) 102 Fi g u r e 32 Creep D e f l e c t i o n data - Parallam PSL -s t r e s s l e v e l 3 (5000 p s i ) 103 x i i ^ PAGE Fi g u r e 33 F r a c t i o n a l Creep data - 1650F Douglas-f i r s t r e s s l e v e l 1 (2060 p s i ) 104 F i g u r e 34 F r a c t i o n a l Creep data - 2400F Douglas-f i r s t r e s s l e v e l 1 (3000 p s i ) 105 F i g u r e 35 F r a c t i o n a l Creep data - Parallam PSL-s t r e s s l e v e l 1 (4000 p s i ) 106 Fig u r e 36 F r a c t i o n a l Creep data - 1650F Douglas-f i r s t r e s s l e v e l 2 (2325 p s i ) 107 F i g u r e 37 F r a c t i o n a l Creep data - 2400F Douglas-f i r s t r e s s l e v e l 2 (2325 p s i ) 108 F i g u r e 38 F r a c t i o n a l Creep data - Parallam PSL -s t r e s s l e v e l 2 (4500 p s i ) 109 F i g u r e 39 F r a c t i o n a l Creep data - 1650F Douglas-f i r s t r e s s l e v e l 3 (2575 p s i ) 110 F i g u r e 40 F r a c t i o n a l Creep data - 2400F Douglas-f i r s t r e s s l e v e l 3 (3375 p s i ) I l l Fig u r e 41 F r a c t i o n a l Creep data - Parallam PSL -s t r e s s l e v e l 3 (5000 p s i ) 112 Figure 42 Average Creep d e f l e c t i o n vs l i n e a r l i n e a r time - a l l t e s t groups 113 Fig u r e 43 Average Creep d e f l e c t i o n vs l o g time -a l l t e s t groups 114 Figure 44 Average F r a c t i o n a l Creep v s l i n e a r time f o r a l l s t r e s s l e v e l 1 groups 115 F i g u r e 45 Average F r a c t i o n a l Creep vs l i n e a r time f o r a l l s t r e s s l e v e l 2 groups 116 Fig u r e 46 Average F r a c t i o n a l Creep vs l i n e a r time f o r a l l s t r e s s l e v e l 3 groups 117 Fig u r e 47 Average F r a c t i o n a l Creep v s l o g time f o r f o r a l l s t r e s s l e v e l 1 groups 118 F i g u r e 48 Average F r a c t i o n a l Creep vs l o g time f o r f o r a l l s t r e s s l e v e l 2 groups 119 F i g u r e 49 Average F r a c t i o n a l Creep vs l o g time f o r f o r a l l s t r e s s l e v e l 3 groups 120 x i i i PAGE F i g u r e 50 S u r v i v a l P r o b a b i l i t y curves f o r 1650F D o u g l a s - f i r s t r e s s l e v e l s 1,2 and 3 ... 121 F i g u r e 51 S u r v i v a l P r o b a b i l i t y curves f o r 2400F D o u g l a s - f i r s t r e s s l e v e l s 1,2 and 3 ... 122 F i g u r e 52 S u r v i v a l P r o b a b i l i t y curves f o r Parallam PSL D o u g l a s - f i r - s t r e s s l e v e l s 1,2 and 3 123 F i g u r e 53 Cumulative frequency d i s t r i b u t i o n s of MOR f o r s u r v i v i n g specimens from DOL study -1650F D o u g l a s - f i r 124 F i g u r e 54 Cumulative frequency d i s t r i b u t i o n s of MOR f o r s u r v i v i n g specimens from DOL study -2400F D o u g l a s - f i r 125 F i g u r e 55 Cumulative frequency d i s t r i b u t i o n s of MOR f o r s u r v i v i n g specimens from DOL study -Parallam PSL 126 F i g u r e 56 C a l c u l a t e d s t e s s r a t i o s using sh o r t term s t r e n g t h c o n t r o l specimens 127 F i g u r e 57 C a l c u l a t e d s t r e s s r a t i o s using s u r v i v i n g specimens from l o n g term l o a d study.... 128 F i g u r e 58 Comparison of Average F r a c t i o n a l Creep r e -s u l t s between s t r e s s l e v e l s - 1650F D o u g l a s - f i r 129 F i g u r e 59 Comparison of Average F r a c t i o n a l Creep r e -s u l t s between s t r e s s l e v e l s - 2400F Douglas f i r 130 F i g u r e 60 Comparison of Average F r a c t i o n a l Creep r e s u l t s between s t r e s s l e v e l s -Parallam PSL 131 F i g u r e 61 Comparison of observed average d e f l e c t i o n with p r e d i c t e d average d e f l e c t i o n from creep models-1650F, D o u g l a s - f i r 132 F i g u r e 62 Comparison of observed average d e f l e c t i o n with p r e d i c t e d average d e f l e c t i o n from creep models-2400F, Douglas f i r 133 F i g u r e 63 Comparison of observed average d e f l e c t i o n with p r e d i c t e d average d e f l e c t i o n from creep models - Parallam PSL 134 xiv PAGE F i g u r e 64 Comparison of observed r e l a t i v e creep with p r e d i c t e d r e l a t i v e creep from creep models, 1650F, D o u g l a s - f i r , S L l 135 Fi g u r e 65 Comparison of observed r e l a t i v e creep w i t h p r e d i c t e d r e l a t i v e creep from creep models, 1650F, D o u g l a s - f i r , SL2 136 Fi g u r e 66 Comparison of observed r e l a t i v e creep with p r e d i c t e d r e l a t i v e creep from creep models, 1650F, D o u g l a s - f i r , SL3 137 Fi g u r e 67 Comparison of observed r e l a t i v e creep w i t h p r e d i c t e d r e l a t i v e creep from creep models, 2400F, D o u g l a s - f i r , S L l 138 Fi g u r e 68 Comparison of observed r e l a t i v e creep with p r e d i c t e d r e l a t i v e creep from creep models, 2400F, D o u g l a s - f i r , SL2. 139 Fi g u r e 69 Comparison of observed r e l a t i v e creep with p r e d i c t e d r e l a t i v e creep from creep models, 2400F, D o u g l a s - f i r , SL3 140 F i g u r e 70 Comparison of observed r e l a t i v e creep with p r e d i c t e d r e l a t i v e creep from creep models, Parallam PSL, S L l 141 Fi g u r e 71 Comparison of observed r e l a t i v e creep w i t h p r e d i c t e d r e l a t i v e creep from creep models, Parallam PSL, SL2 142 Fi g u r e 72 Comparison of observed r e l a t i v e creep with p r e d i c t e d r e l a t i v e creep from creep models, Parallam PSL, SL3 143 F i g u r e 73 L i n e a r r e g r e s s i o n a n a l y s i s of power model c o e f f i c i e n t A vs s h e a r - f r e e modulus of e l a s t i c i t y , MOEt 144 F i g u r e 74 L i n e a r r e g r e s s i o n a n a l y s i s of power model c o e f f i c i e n t B vs s h e a r - f r e e modulus of e l a s t i c i t y , MOEt 145 Fi g u r e 75 L i n e a r r e g r e s s i o n a n a l y s i s of l i n e a r v i s -c o e l a s t i c model parameter b3 vs shear-f r e e modulus of e l a s t i c i t y , MOEt 146 F i g u r e 76 L i n e a r r e g r e s s i o n a n a l y s i s of l i n e a r v i s -c o e l a s t i c model parameter be vs shear-f r e e modulus of e l a s t i c i t y MOEt 147 F i g u r e 77 L i n e a r r e g r e s s i o n a n a l y s i s of l i n e a r v i s -c o e l a s t i c model parameter bg vs shear-f r e e modulus of e l a s t i c i t y MOEt 148 XV A C K N O W L E D G E M E N T S The author wishes to thank Dr. J.D. B a r r e t t , Department of F o r e s t r y , U n i v e r s i t y of B r i t i s h Columbia and Dr. R.O.Foschi, 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 f o r t h e i r suggestions and c r i t i c a l review of t h i s work. S p e c i a l acknowledgement given t o the Parallam D i v i s i o n of MacMillan B l o e d e l L i m i t e d f o r p e r m i t t i n g t h i s work to be p u b l i s h e d . I a l s o wish to thank Mr. B. T a y l o r of the Parallam D i v i s i o n f o r h i s a s s i s t a n c e w i t h the computer program m o d i f i c a t i o n s and a l s o t o Ms. M. de l a Cruz f o r the t y p i n g of the manus-c r i p t . 1 CHAPTER ONE INTRODUCTION 1.1 Background W i t h t h e c h a n g i n g f o r e s t r e s o u r c e b a s e i n N o r t h A m e r i c a , t h e r e has been a renewed e f f o r t i n r e c e n t y e a r s by government , i n d u s t r y s p o n s o r e d r e s e a r c h l a b o r a t o r i e s and by f o r e s t p r o d u c t s companies t o develop h i g h e r end-value products from lower grade raw m a t e r i a l s . Examples of p r o d u c t s making s u c h i n r o a d s w i t h i n the s t r u c t u r a l wood markets are o r i e n t e d s t r a n d b o a r d (OSB) and l a m i n a t e d v e n e e r lumber (LVL). These p r o d u c t s o f f e r improved s t r e n g t h p r o p e r t i e s through a s i g n i f i c a n t r e d u c t i o n i n v a r i a b i l i t y i n t h e i r m e c h a n i c a l p r o p e r t i e s . Another example of t h e s e new s t r u c t u r a l c o m p o s i t e lumber p r o d u c t s i s a p r o d u c t d e v e l o p e d by M a c M i l l a n B l o e d e l L i m i t e d , V ancouver, i Canada c a l l e d Parallam® p a r a l l e l s t r a n d lumber (PSL). P a r a l l a m i s a h i g h l y u n i f o r m , e n g i n e e r e d s t r u c t u r a l m a t e r i a l manufactured by l a m i n a t i n g long, t h i n Douglas-f i r veneer strands. The veneer strands a r e coated w i t h an e x t e r i o r - t y p e phenol formaldehyde r e s i n , l a y e r e d i n 1 a r e g i s t e r e d trademark of MacMillan B l o e d e l L i m i t e d 2 a mat o r i e n t e d t o t h e l e n g t h of the beam and f e d i n t o a p r e s s where i t i s c u r e d under h e a t and p r e s s u r e . The p r o d u c t i s m a n u f a c t u r e d i n a c o n t i n u o u s p r o c e s s i n c u r r e n t l y a nominal 8"xl5" c r o s s - s e c t i o n which can then be c r o s s - c u t and r i p p e d to the d e s i r e d s t r u c t u r a l s i z e s ( F i g . l ) . P a r a llam i s c u r r e n t l y being manufactured i n a 95,000 sq. f t . p r o t o t y p e p l a n t where the c o m m e r c i a l f e a s i b i l i t y of the product i s being evaluated. W i t h t h e d e v e l o p m e n t of any new s t r u c t u r a l wood product, e x t e n s i v e t e s t i n g i s r e q u i r e d t o e s t a b l i s h i t s p h y s i c a l and m e c h a n i c a l p r o p e r t i e s . Such a t e s t program has been conducted by M a c M i l l a n B l o e d e l and has i n c l u d e d the f o l l o w i n g t e s t s : • f l e x u r e • t e n s i o n p a r a l l e l to g r a i n • compression p a r a l l e l to g r a i n • compression p e r p e n d i c u l a r to g r a i n • shear p a r a l l e l to g r a i n • mechanical f a s t e n e r s ( n a i l s , b o l t s , t r u s s p l a t e s ) • f i r e performance • d u r a t i o n of l o a d / c r e e p The r e s u l t s of t h i s t e s t program have been summarized i n a number of r e p o r t s i s s u e d by v a r i o u s b u i l d i n g code agencies which e s t a b l i s h the a l l o w a b l e design s t r e s s e s f o r Parallam. An example code r e p o r t i s shown i n F i g . 2 . 3 Design C o n s i d e r a t i o n s . The d e s i g n o f s t r u c t u r a l members o r a s s e m b l i e s g e n e r a l l y i n v o l v e s two major e n g i n e e r i n g p r o b l e m s a r i s i n g out of the loads t h a t members are expected to support. One i s deformation which can be r e s t r i c t e d f o r f u n c t i o n a l or a e s t h e t i c reasons and, the other i s , the avoidance of f a i l u r e . I t has long been r e c o g n i z e d t h a t wood under l o a d l o s e s s t r e n g t h w i t h t i m e ( d u r a t i o n of l o a d (DOL) e f f e c t ) and c o n t i n u e s to def o r m w i t h t i m e ( c r e e p ) . Both a r e m a n i f e s t a t i o n s of t h e l o a d - t i m e r h e o l o g i c a l b e h a v i o u r of wood and must be c o n s i d e r e d when d e s i g n i n g s t r u c t u r e s with wood. The e f f e c t of d u r a t i o n of l o a d has been i n c o r p o r a t e d i n t h e t i m b e r d e s i g n codes as an a d j u s t m e n t f a c t o r a p p l i e d to allowable s t r e s s e s a c c o r d i n g t o v a l u e s i n F i g . 3 ( l ) . T h i s curve, known as the 'Madison curve* i s p r i m a r i l y based on the r e s u l t s of r a t e - o f -l o a d i n g and c o n s t a n t - l o a d t e s t s on s m a l l , c l e a r , s t r a i g h t g r a i n specimens evaluated i n bending and combined w i t h e n g i n e e r i n g judgement t o extend the curve beyond the time p e r i o d i n v e s t i g a t e d (2). This curve has been a r b i t r a r i l y extended t o o t h e r c l e a r wood s t r e n g t h p r o p e r t i e s and other s t r u c t u r a l wood products i n c l u d i n g wood composites (3) . In recent y e a r s , s e v e r a l DOL research programs have been i n i t i a t e d as p a r t of the "in-grade" t e s t program designed t o evaluate the s t r u c t u r a l performance of 4 lumber as produced. R e s u l t s from these s t u d i e s have i n d i c a t e d t h a t the DOL response of dimension lumber d i f f e r s from that of sma l l , c l e a r specimens (4). An example of t h i s i s the r e s u l t s r e p o r t e d by F o s c h i and B a r r e t t (4) f o r nominal 2x6 western hemlock lumber i n bending shown i n F i g u r e 4. Included f o r com-p a r i s o n i n F i g u r e 4 are the standard ( h y p e r b o l i c ) Madison curve and the l i n e a r t r e n d l i n e from the Madison experiment as i n i t i a l l y presented by Wood(2). Recognizing these d i f f e r e n c e s based on the e v a l u a t i o n of the DOL e f f e c t f o r f u l l - s i z e s t r u c t u r a l lumber, the v a l i d i t y of e x t e n d i n g t h e p r e s e n t DOL a d j u s t m e n t f a c t o r s t o a newly-developed s t r u c t u r a l wood composite product such as Parallam, must be v e r i f i e d . Deformation i s c o n t r o l l e d i n the timber design codes through use of maximum d e f l e c t i o n l i m i t s which vary d e p e n d i n g on t h e t y p e of c o n s t r u c t i o n . T h e c o n t r i b u t i o n o f c r e e p d e f o r m a t i o n t o t h e t o t a l d eformation i s only l o o s e l y addressed i n the codes where e x p l i c i t c o n s i d e r a t i o n of creep i s g e n e r a l l y l e f t to the d e c i s i o n of the de s i g n e r (1). North American codes accept the general g u i d e l i n e that creep i s one-half of the dead l o a d i n s t a n t a n e o u s e l a s t i c d e f l e c t i o n f o r seasoned lumber and equal to the dead l o a d e l a s t i c d e f l e c t i o n f o r uns e a s o n e d lumber. Creep b e h a v i o u r of s t r u c t u r a l wood products 5 can vary c o n s i d e r a b l y depending on temperature and moisture c o n d i t i o n s and i t i s g e n e r a l l y r e c o g n i z e d t h a t c r e e p b e h a v i o u r i n wood c o m p o s i t e s can d i f f e r t o t h a t of s o l i d wood (5). F a c t o r s such as t h e nature of i t s manufacture and i t s response t o changing temperature and humidity make i t necessary t o e v a l u a t e t h e c r e e p b e h a v i o u r of new s t r u c t u r a l lumber composites. The t e s t p r o g r a m f o r P a r a l l a m o u t l i n e d e a r l i e r r e c o g n i z e s t h e f a c t t h a t i n t h e e v a l u a t i o n of any new s t r u c t u r a l wood composite, d e t e r m i n a t i o n of i t s l o n g -term creep/rupture performance i s a necessary p a r t of t h a t program. T h i s s t u d y s u m m a r i z e s t h e r e s u l t s of a c o m p a r i s o n c r e e p / r u p t u r e study c o n d u c t e d on P a r a l l a m and two groups of s t r u c t u r a l D o u g l a s - f i r lumber. 1.2 O b j e c t i v e s The o b j e c t i v e s of t h i s r e s e a r c h were: 1. determine the c r e e p / d u r a t i o n of l o a d performance i n bending of Pa r a l l a m PSL and compare i t to two groups of D o u g l a s - f i r l u m b e r f o r t h r e e d i f f e r e n t s t r e s s l e v e l s i n an u n c o n t r o l l e d i n t e r i o r environment. 2. t o model the c r e e p p e r f o r m a n c e o b s e r v e d f o r the P a r a l l a m and D o u g l a s - f i r m a t e r i a l t e s t e d and compare these r e s u l t s w i t h the creep behaviour of other s t r u c t u r a l wood products r e p o r t e d i n the 6 l i t e r a t u r e . 1.3 T e s t Design The chosen t e s t d e s i g n compared t h e d u r a t i o n of l o a d and c r e e p p e r f o r m a n c e i n f l e x u r e of P a r a l l a m t o two groups of machine s t r e s s r a t e d (MSR) D o u g l a s - f i r lumber a t three d i f f e r e n t s t r e s s l e v e l s . The m a t e r i a l s i z e i n a l l groups was n o m i n a l 2 nx4"x84" (1.5"x3.5 , ,x84"). The three s t r e s s l e v e l s chosen f o r P a r a l l a m were 4000,4500 and 5000 pounds per s q u a r e i n c h ( p s i ) and range from 25% to 56% above the product's a l l o w a b l e design s t r e s s (3200 p s i f o r 2"x4" s i z e s , see F i g u r e 2 ) . The s t r e s s l e v e l s c hosen f o r t h e two D o u g l a s - f i r MSR groups were 3000, 3375 and 3750 p s i f o r the 2400F, 2.0E group and 2060, 2325 and 2575 p s i f o r t h e 1650F, 1.5E group. These s t r e s s l e v e l v a l u e s were chosen such t h a t each t e s t group i s s t r e s s e d t o the same m u l t i p l e of i t s a l l o w a b l e d e s i g n s t r e s s as t h e P a r a l l a m m a t e r i a l . A summary of the s t r e s s l e v e l v a l u e s f o r each t e s t group i s given below: i M a t e r i a l Allowable Design S t r e s s L e v e l (psi) Type S t r e s s e s 1 2 3 Parallam D. f i r D. f i r Load f a c t o r 3200F, 2.0E 2400F, 2.0E 1650F, 1.5E 4000 4500 5000 3 0 0 0 3 3 7 5 3750 2060 2325 2 5 7 5 1 . 2 5 0 1 . 4 0 6 1 . 5 6 3 2sample s i z e of 34 per c e l l 3 a l l o w a b l e bending s t r e s s i n p s i ^ o d u l u s of e l a s t i c i t y ( xlO^psi) r a t i o of a p p l i e d s t r e s s t o a l l o w a b l e bending s t r e s s 7 Machine s t r e s s r a t e d D o u g l a s - f i r lumber was chosen as th e c o n t r o l s i n c e P a r a l l a m w i l l be used i n s i m i l a r a p p l i c a t i o n s t o t h i s m a t e r i a l . A sample s i z e of 34 t e s t s p e c i m e n s per t e s t c e l l was c h o s e n t o y i e l d a t o t a l s a m p l e s i z e o f 306. The o b j e c t i v e was t o have a sample s i z e l a r g e enough t o permit s t a t i s t i c a l a n a l y s e s but a t the same time, s m a l l enough so warehouse space r e n t a l and t e s t equipment c o s t s were not p r o h i b i t i v e . The l o a d environment chosen f o r t h i s study was t h a t of an u n c o n t r o l l e d i n t e r i o r e n v i r o n m e n t . T h i s type of e n v i r o n m e n t i s c o n s i d e r e d t y p i c a l of many of t h e l o c a t i o n s i n which Parallam w i l l be used. 8 CHAPTER TWO T H E O R Y 2.1 Creep 2.1.1 Creep Terms L i k e most s t r u c t u r a l m a t e r i a l s , wood deforms i n s t a n t a n e o u s l y when loaded and continues to deform under a s u s t a i n e d l o a d . T h i s time-dependent deformation i s c a l l e d creep. Example p l o t s of creep deformation f o r wood-based m a t e r i a l s a r e i l l u s t r a t e d i n F i g u r e 5 and demonstrate the p o s s i b l e deformation responses t o an a p p l i e d l o a d . When a l o a d , P, i s a p p l i e d t o a wood member, an instantaneous d e f l e c t i o n , So r e s u l t s . The r e s u l t i n g creep d e f l e c t i o n , 6 C , i s dependent on time and the magnitude of the a p p l i e d l o a d . If the a p p l i e d l o a d i s low enough r e l a t i v e to the members' breaking s t r e n g t h , say Pi i n Fi g u r e 5, then a time-deformation p l o t with r e s u l t i n g deforma-t i o n , 6i , r e s u l t s ( 6i> <5o) a t some l a t e r time, t . If the a p p l i e d l o a d i s doubled (Pi=2P 2) and the r e s u l t i n g deformation, 6 2, doubles then the time-deformation response e x h i b i t s l i n e a r r h e o l o g i c a l behaviour. These two creep deformation curves e x h i b i t two stages of creep d e f i n e d as primary creep (rate of deformation i s decreasing) and secondary creep (rate of deformation i s c o n s t a n t ) . 9 If the a p p l i e d l o a d i s high enough ( P 3 ) , then a t some l a t e r time, t , a t h i r d stage of creep known as t e r t i a r y c reep w i l l r e s u l t where the r a t e of deform-a t i o n i n c r e a s e s e v e n t u a l l y l e a d i n g t o f a i l u r e , perhaps at some c r i t i c a l d e formation, 63 . In t h i s study, both primary and secondary creep behaviour i s expected f o r the l o a d l e v e l s a p p l i e d and the l e n g t h of time the t e s t m a t e r i a l w i l l be under l o a d . Some of the mostly h i g h l y s t r e s s e d specimens may e x h i b i t the t e r t i a r y creep response and e v e n t u a l l y f a i l under the c o n s t a n t a p p l i e d l o a d s . The time-deformation response o b t a i n e d w i l l be examined t o determine i f l i n e a r r h e o l o g i c a l behaviour i s e x h i b i t e d . From the time-deformation p l o t s i n F i g u r e 5, one can see t h a t the t o t a l d e f l e c t i o n , <5(t) i s determined from two c o n t r i b u t i o n s , (1) the instantaneous d e f l e c t i o n , 6 o and (2) the creep d e f l e c t i o n , 6 c ( t ) where 6 ( t ) = 6 0 + 6 c ( t ) (2.1) In order to compare experimental data from d i f f e r e n t sources, i t i s convenient to d e f i n e the term f r a c t i o n a l creep, Cfr a s the r a t i o of t o t a l deform-a t i o n t o i n i t i a l d e f l e c t i o n : C f = 6 ( t ) / 6 0 (2.2) Another term used f r e q u e n t l y i n the l i t e r a t u r e i s r e l a t i v e creep, C r f w h i c h has been d e f i n e d as the r a t i o of creep d e f l e c t i o n t o i n i t i a l d e f l e c t i o n . C r = 6 c (t) = 6 ( t ) - 6 o (2.3) 6 0 6 0 10 The two creep terms are measures of the same behaviour being r e l a t e d by the simple e x p r e s s i o n : Cf= 1 + C r (2.4) In t h i s study, the r e s u l t s have been expressed i n terms of f r a c t i o n a l creep, Cf/ however, when comparison t o the r e s u l t s of other s t u d i e s i s made the r e l a t i v e creep term, C r/ i s used. Creep i s a l s o commonly q u a n t i f i e d by the "creep compliance", J ( t ) which i s d e f i n e d a s : J ( t ) = s t r a i n (at time t ) e ( t ) (2.5) a p p l i e d constant s t r e s s 0 A p l o t of the creep compliance a g a i n s t s t r e s s as a f u n c t i o n of the short-term s t r e s s i s used t o i n d i c a t e the nature of the r h e o l o g i c a l behaviour. If the p l o t i s l i n e a r , then l i n e a r r h e o l o g i c a l behaviour i s i n d i c a t e d . T h i s i s u s e f u l when a p p l y i n g models t o creep behaviour. 2.1.2 F a c t o r s A f f e c t i n g Creep The magnitude of creep deformation observed i s dependent on a number of parameters and these have been summarized i n the l i t e r a t u r e by many r e s e a r c h e r s (6, 7, 8). These parameters i n c l u d e - (1) time, t , (2) a p p l i e d s t r e s s , o r (3) temperature, T , (4) moisture content,%MC ( r e l a t i v e humidity, %RH) , (5) previous l o a d h i s t o r y , (6) specimen volume, V, and 11 (7) the property e v a l u a t e d and method of measurement. The nature of the creep response to the f i r s t f i v e parameters i s summarized i n F i g u r e 6. The specimen volume i n f l u e n c e s creep deformation i n two ways: (1) temperature and moisture content g r a d i e n t s are a f u n c t i o n of specimen volume and f (2) s i z e e f f e c t where the g r e a t e r the volume, the more l i k e l y the p r o b a b i l i t y of the presence of s t r e n g t h reducing f l a w s i n the m a t e r i a l which w i l l a f f e c t creep deformation. L a s t l y , the method of measurement depends on the m a t e r i a l property being s t u d i e d ( i . e . , f l e x u r e , t e n s i o n or s h e a r ) . For f l e x u r e , the creep deformation response i s f u r t h e r dependent on the beam span-to-depth r a t i o where d i f f e r e n t shear c o n t r i b u t i o n s to the t o t a l bending creep deformation could be present. In t h i s study, the pure bending creep d e f o r m a t i o n 1 observed w i l l be e s s e n t i a l l y a f u n c t i o n of time and s t r e s s f o r a f i x e d specimen volume and method of measurement. 2 There w i l l a lso be secondary c o n t r i -b u t i o n s due to changing r e l a t i v e humidity and temperature d i c t a t e d by d a i l y and seasonal c l i m a t i c changes w i t h i n the t e s t environment. As s t a t e d p r e v i o u s l y , the o b j e c t i v e of t h i s study i s not to i s o l a t e out a l l parameters but rather to measure the creep response of the t e s t m a t e r i a l s i n an environment s i m i l a r to a c t u a l end use c o n d i t i o n s . 1 D e f l e c t i o n s were measured i n the constant moment r e g i o n of a bending specimen 2 Midspan d e f l e c t i o n was measured with respect to gauge p o i n t s w i t h i n the constant moment zone. 12 2.2 Mathematical Models of Creep 2.2.1 E m p i r i c a l Curve F i t t i n g - Power Model A common approach to mo d e l l i n g creep behaviour i s e m p i r i c a l curve f i t t i n g i n which an a p p r o p r i a t e equation i s chosen to d e s c r i b e the data. The parameters of the equation are determined e i t h e r g r a p h i c a l l y or by a s u i t a b l e s t a t i s t i c a l t e c hnique and u s u a l l y can not be r e l a t e d t o p h y s i c a l p r o p e r t i e s of the m a t e r i a l . A number of equations have been used t o d e s c r i b e creep behaviour (5, 6 ) , one of the most common being the "power f u n c t i o n " model. T h i s model has been chosen i n the study to i l l u s t r a t e the e m p i r i c a l approach t o mode l l i n g creep behaviour. The "power f u n c t i o n " model assumes t h a t creep behaviour f o l l o w s a curve with the form: 6(t) = 6 o d + A t B ) where (2.6) 6(t) = d e f l e c t i o n a t time, t <5o = i n i t i a l d e f l e c t i o n 1 t = time A, B = constants Expressed i n terms of r e l a t i v e creep, C r , t h e equation takes the form: C r = A t B (2.7) Taking l o g a r i t h m s g i v e s : l o g (C r) = Log A + B l o g t (2.8) i For t h i s study the d e f l e c t i o n , <5o W a s t a k e n t o be the measured d e f l e c t i o n a t t=lmin. from the time the f u l l l o a d was a p p l i e d . 1 3 By p l o t t i n g the l o g ( C r ) vs l o g t f the slope of the p l o t i s B and the i n t e r c e p t of the s t r a i g h t l i n e i s l o g A. Because the transformed r e l a t i o n s h i p i s l i n e a r , the parameters can be determined from using standard l i n e a r l e a s t - s q u a r e s curve f i t t i n g t e c h n i q u e s . Once the parameters have been c a l c u l a t e d , the curve can be p l o t t e d and compared to the experimental data. 2.2.2 L i n e a r V i s c o e l a s t i c Model M a t e r i a l s that e x h i b i t creep behaviour are c a l l e d v i s c o e l a s t i c m a t e r i a l s , t h a t i s , they e x h i b i t time dependent behaviour. T h i s behaviour can be i n t e r -p r e t e d w i t h the a i d of mechanical models comprising d i f f e r e n t combinations of s p r i n g s and d a s h p o t s ( 5 ) . The s p r i n g element a c t s as a mechanical analogue of the e l a s t i c component of deformation w h i l e the dashpot element simulates the v i s c o u s component. G e n e r a l i z e d models are developed by combining s p r i n g and dashpot elements i n t o systems of s e r i e s and p a r a l l e l components. If these systems are l i n e a r i n t h e i r behaviour, ( i . e . , the deformation a t time t , i t i s d i r e c t l y p r o p o r t i o n a l to the a p p l i e d s t r e s s ) , then the model d e s c r i b e s l i n e a r v i s c o e l a s t i c behaviour. One of the s i m p l e s t , l i n e a r v i s c o e l a s t i c models which has been found to simulate the time-dependent behaviour i n wood-materials ( 9 ) i s the f o u r element model shown below: 14 rVWWVS k2 WW" .«. n2 T h i s model combines one set of s p r i n g and dashpot elements i n s e r i e s and a second s e t i n p a r a l l e l . The t o t a l deformation of the model ( 6(t)) i s d e s c r i b e d mathematically by the f o l l o w i n g e q u a t i o n : 6(t) = b x + b 2 d - e x p [ - b 3 t ] ) + b 4 t (2.9) where 6(t) = i s the t o t a l d e f l e c t i o n t = time b-L,b2/b3rb4 = c o n s t a n t s The p h y s i c a l i n t e r p r e t a t i o n of each of these terms i s as f o l l o w s : b j = i s a term r e p r e s e n t i n g instantaneous deformation a s s o c i a t e d with s p r i n g constant k j k>2(1-exp [-b3t]) = i s a term r e p r e s e n t i n g delayed e l a s t i c i t y o c c u r r i n g d u r i n g primary and secondary stages of creep and i s a s s o c i a t e d with s p r i n g constant k 2 and dashpot damping c o e f f i c i e n t n2 * b 4 t = i s a term r e p r e s e n t i n g v i s c o u s flow during the secondary stage of creep and i s a s s o c i a t e d w i t h dashpot damping c o e f f i c i e n t r»3' Equation (2.9) re-arranged to express r e l a t i v e creep, C r g i v e s : C r = b 5 ( l - e x p [ - b 3 t ] ) + b 6 t where b 5 = b 2 / b 1  b 6 = b 4 / b l (2.10) (2.11) (2.12) 15 Determination of the parameters that best f i t the creep d e f l e c t i o n data r e q u i r e s a n o n - l i n e a r curve f i t t i n g procedure because of the n o n - l i n e a r b3 term. In t h i s study , the creep d e f l e c t i o n data was f i t t e d to equation (2.9) using the n o n - l i n e a r f u n c t i o n o p t -i m i z a t i o n program(DFMIN) s u p p l i e d by the UBC Computing Centre. Once the terms bi to b 4 were determined, the terms f o r the r e l a t i v e creep equation, b^ and bg were c a l c u l a t e d u sing equations (2.11) and (2.12) r e s p e c t i v e l y . The use of a l i n e a r v i s c o e l a s t i c model to d e s c r i b e creep behaviour i s c a l l e d a phenomenological approach, i n t h a t , i t i s only the phenomena e x h i b i t e d by the two systems t h a t are e q u i v a l e n t , not t h e i r i n h e r e n t processes themselves. To i n f e r s t r u c t u r e of the m a t e r i a l from the s t r u c t u r e of the model can be m i s l e a d i n g . CHAPTER THREE 16 EXPERIMENTAL 3.1 T e s t M a t e r i a l s 3.1.1 D o u g l a s - f i r The D o u g l a s - f i r t e s t m a t e r i a l was c o m m e r c i a l l y a v a i l a b l e machine s t r e s s r a t e d (MSR) lumber purchased from m i l l s l o c a t e d i n t h e P a c i f i c N o r t h w e s t r e g i o n of t h e U n i t e d S t a t e s . The lumber was purchased as nominal 2 by 4 i n c h s e c t i o n s and i n l e n g t h s ranging from 10 f t . to 18 f t . Two packages of 208 p i e c e s stamped 2400F f 2.0E MSR and t h r e e packages of 208 p i e c e s stamped 1650F, 1.5E MSR were o b t a i n e d f o r the study. Each package came from a d i f f e r e n t s u p p l i e r , t h e r e f o r e , a d i f f e r e n t lumber m i l l . Only one m i l l was represented i n both the 2400F and 1650F grades. No regrading of the m a t e r i a l was under-taken. Each package was c o n s i d e r e d to be r e p r e s e n -t a t i v e of the product grade c u r r e n t l y being marketed. The Parallam t e s t m a t e r i a l was manufactured i n December 1983 by the P a r a l l a m D i v i s i o n of M a c M i l l a n B l o e d e l L i m i t e d i n a Prototype Plant f a c i l i t y l o c a t e d on Annacis I s l a n d , D e l t a , B.C. The t e s t m a t e r i a l was p a r t of a sample s e l e c t e d f o r a l a r g e r study designed t o determine the allowable design p r o p e r t i e s f o r the product f o r submission to model code agencies i n Canada and the U.S. 3.1.2 Parallam P.S.L. 17 A l l t e s t m a t e r i a l was m a n u f a c t u r e d as a 4 i n . x 12 i n . b i l l e t of continuous l e n g t h and remanufactured i n t o t e s t s i z e s of n o m i n a l 2"x4 nx84" (1.5 i n . x 3.5 i n . x 84 i n . ) The t e s t m a t e r i a l was c o n s i d e r e d r e p r e s e n t a t i v e p r o d u c t i o n f r o m t h i s p l a n t a s e s t a b l i s h e d by t h e i n -house q u a l i t y assurance program. 3.2 M a t e r i a l P r e p a r a t i o n 3.2.1 Sampling From each 1650F,1.5E D o u g l a s - f i r package, 57 p i e c e s of l u m b e r w e r e r a n d o m l y s a m p l e d a n d c u t b a c k t o 84" lengths. T h i s p r o v i d e d a t o t a l of 171 t e s t p i e c e s to be s u b d i v i d e d i n t o specimens f o r short term f l e x u r e (66 p i e c e s ) and l o n g term l o a d t e s t s (102 p i e c e s ) with three spare. From each 2400F, 2.0E D o u g l a s - f i r package, 87 p i e c e s of lumber were randomly sampled and c u t back t o 84" i n length. T h i s a g a i n p r o v i d e d a t o t a l of 174 t e s t p i e c e s a l l o c a t e d to short term f l e x u r e t e s t s (69 p i e c e s ) and l o n g term l o a d t e s t s (102 p i e c e s ) with t h r e e spare. Test m a t e r i a l with severe t w i s t i n g was not i n c l u d e d i n study. P a r a l l a m t e s t m a t e r i a l f o r t h i s study was sampled from the l a r g e r "code a p p r o v a l " t e s t p o p u l a t i o n m e n t i o n e d p r e v i o u s l y by t h e method o u t l i n e d i n t h e P o p u l a t i o n D i v i s i o n s e c t i o n . 18 3.2.2 C o n d i t i o n i n g A l l P a r a l l a m and D o u g l a s - f i r t e s t m a t e r i a l were c o n d i t i o n e d f o r a minimum s i x - w e e k p e r i o d i n a 65% r e l a t i v e humidity (RH) and 21°C c o n d i t i o n i n g room p r i o r to p o p u l a t i o n d i v i s i o n . A c c o r d i n g t o the Wood Handbook, D o u g l a s - f i r lumber should a c h i e v e an e q u i l i b r i u m m o i s t u r e c o n t e n t (E.M.C.) of 12% i n t h i s e n v i r o n m e n t . The a c t u a l moisture contents o b t a i n e d f o r the s h o r t term f l e x u r e t e s t m a t e r i a l are summarized below: Short Term F l e x u r e - %MC a t T e s t 1650F r 1.5E 2400F, 2.0E Parallam D o u g l a s - f i r D o u g l a s - f i r PSL Average 12.7 13.1 12.7 (%CV) 10.6 5.9 12.6 Maximum 15.4 15.0 15.6 Minimum 7.2 11.8 9.3 3.2.3 P o p u l a t i o n D i v i s i o n S e v e r a l t e c h n i q u e s a r e a v a i l a b l e w h i c h a t t e m p t t o s t r e n g t h match t e s t beams i n s h o r t and l o n g term l o a d i n g s t u d i e s and t h e r e b y make i t p o s s i b l e t o i n t e r p r e t d u r a t i o n of l o a d e f f e c t s . Two common approaches are the " m a t c h e d s p e c i m e n " t e c h n i q u e a n d t h e " m a t c h e d d i s t r i b u t i o n " t e c h n i q u e . For s t r u c t u r a l s i z e lumber s p e c i m e n s , th e "matched d i s t r i b u t i o n " t e c h n i q u e i s c o n s i d e r e d to be the more p r a c t i c a l approach and was the technique used i n t h i s study. 19 D o u g l a s - f i r F o l l o w i n g c o n d i t i o n i n g , t h e 171 p i e c e s of 1650F, 1.5E D o u g l a s - f i r and 174 p i e c e s o f 2400F, 2.0E D o u g l a s - f i r were p r o o f - t e s t e d on edge i n t h i r d - p o i n t l o a d i n g (21:1 s p a n : d e p t h r a t i o ) t o a s t r e s s o f 1175 p s i . The apparent modulus of e l a s t i c i t y (MOEa) was c a l c u l a t e d f o r each t e s t beam. From p r e v i o u s t e s t work, an a p p l i e d s t r e s s of 1175 p s i was found t o be no more than 50% of the p r o p o r t i o n a l l i m i t s t r e s s of the weakest p i e c e i n the t e s t p o p u l a t i o n . T h i s was a l s o found t o be the case i n t h i s study. Based on the c a l c u l a t e d modulus of e l a s t i c i t y values, a l l the t e s t beams f o r each D o u g l a s - f i r group to be used i n the sh o r t and l o n g term l o a d i n g s t u d i e s were ranked from weakest to s t r o n g e s t . The one hundred and seventy plus t e s t beams f o r each D o u g l a s - f i r group was sub-d i v i d e d i n t o 34 b l o c k s w i t h 5 beams i n each block p l u s one remaining b l o c k c o n t a i n i n g the remaining number of beams. From each block, the 5 beams were a s s i g n e d t o the f o l l o w i n g c a t e g o r i e s : • s h o r t term f l e x u r e - 2 t e s t beams • l o n g term c r e e p / f l e x u r e s t r e s s l e v e l one - 1 t e s t beam s t r e s s l e v e l two - 1 t e s t beam s t r e s s l e v e l three - 1 t e s t beam The above procedure i s i l l u s t r a t e d g r a p h i c a l l y i n F i g u r e 7. The average MOEa v a l u e s f o r each t e s t group are 20 summarized i n T a b l e 1. Parallam PSL The Parallam p o p u l a t i o n d i v i s i o n procedure d i f f e r e d from the D o u g l a s - f i r procedure f o r the f o l l o w i n g reason: the s h o r t term f l e x u r e and l o n g term cre e p / r u p t u r e study m a t e r i a l f o r m e d p a r t of the p o p u l a t i o n of a l a r g e r study designed t o o b t a i n code a p p r o v a l s f o r the product. For the l a r g e r study, p o p u l a t i o n d i v i s i o n work was based on the "matched p o p u l a t i o n " technique u s i n g the dynamic modulus of e l a s t i c i t y (MOEd) as a measure of s t i f f n e s s . T h i s was accomplished by i n d u c i n g a f l a t w i s e v i b r a t i o n on each t e s t beam on a Me t r i g u a r d 3300 E-computer which c h a r a c t e r i s t i c a l l y g i v e s a 10-15% h i g h e r MOE v a l u e compared t o t h e s t a t i c a l l y d e t e r m i n e d MOEa v a l u e . Ranking by MOEd v a l u e s gave the f o l l o w i n g two sub-groups from the l a r g e r t e s t p o p u l a t i o n : • short term f l e x u r e - 60 t e s t p i e c e s • long term creep/rupture - 170 t e s t p i e c e s Further p o p u l a t i o n d i v i s i o n of the l o n g term cr e e p / rupture group i n t o the 3 s t r e s s l e v e l groups was i d e n t i c a l t o the procedure used f o r the D o u g l a s - f i r 21 t e s t m a t e r i a l s except t h a t i n s t e a d of 2 t e s t beams out of 5 i n each block going t o s h o r t term f l e x u r e , they went i n t o two other t e s t groups which d i d not form p a r t of t h i s study. T h i s p o p u l a t i o n d i v i s i o n procedure was not as simple as the one f o r the D o u g l a s - f i r t e s t groups but was d i c t a t e d by the time c o n s t r a i n t s of the l a r g e r study. The procedure i s s t i l l a v a l i d one s i n c e a l l o -c a t i o n of t e s t specimens does not depend on the magnitude of the i n d i v i d u a l MOE v a l u e s but only on the rank w i t h i n the o v e r a l l MOE d i s t r i b u t i o n . The above p o p u l a t i o n d i v i s i o n procedure i s i l l u s t r a t e d g r a p h i c a l l y i n F i g u r e 8. The average MO Ed and MOEa v a l u e s f o r each P a r a l l a m t e s t group a r e summ a r i z e d i n Table 2. 3.3 F l e x u r e T e s t s 3.3.1 Test Method A l l f l e x u r e t e s t i n g c o n d u c t e d i n t h i s study was i n accordance w i t h the ASTM D198 standards " S t a t i c T e s t s of Timbers i n S t r u c t u r a l S i z e s " (10) and i n c l u d e d : 1. n o n - d e s t r u c t i v e f l e x u r e t e s t s f o r p o p u l a t i o n d i v i s i o n MOEa de t e r m i n a t i o n . 2. short term f l e x u r e t e s t s . 3. f l e x u r e t e s t s on the lo n g term l o a d s u r v i v o r s . 22 The method of t e s t i n g was edgewise t h i r d p o i n t l o a d i n g using a 21:1 span/depth r a t i o . A schematic of the t e s t s e t - u p i s shown i n F i g u r e 9. The speed of t e s t i n g was c h o s e n so t h a t t h e a v e r a g e t i m e t o f a i l u r e was 5 minutes. 3.3.2 Test Procedure D u r i n g p o p u l a t i o n d i v i s i o n work, a l l t e s t beams were p l a c e d i n a u n i v e r s a l t e s t i n g m a c h i n e f o r MOEa de t e r m i n a t i o n f o l l o w i n g c o n d i t i o n i n g w i t h the ex c e p t i o n of the Parallam s h o r t term s t r e n g t h t e s t beams (for the reasons mentioned e a r l i e r ) . The choice of which edge of the beam would be i n compression or t e n s i o n when loade d i n t h e t e s t machine was random but once chosen, was i d e n t i f i e d so a l l s u b s e q u e n t l o a d i n g w o u l d be c a r r i e d out the same way. The P a r a l l a m and D o u g l a s - f i r l o n g t e rm l o a d s u r v i v o r s were l o a d e d t o d e s t r u c t i o n i n the same d i r e c t i o n i n which they were l o a d e d i n t h e l o n g t e r m c r e e p / r u p t u r e study. S i m i l a r l y , t h e D o u g l a s - f i r s h o r t term s t r e n g t h t e s t m a t e r i a l was l o a d e d t o d e s t r u c t i o n i n t h e same d i r e c t i o n as they were loade d d u r i n g p o p u l a t i o n d i v i s o n work. For each t e s t beam l o a d e d t o d e s t r u c t i o n , the f o l l o w i n g i n f o r m a t i o n was o b t a i n e d : 1. beam dimensions 2. u l t i m a t e l o a d 23 3. lo a d - d e f o r m a t i o n p l o t 4. time t o f a i l u r e 5. d e s c r i p t i o n of f a i l u r e 6. beam moisture content 3.4 Long Term Creep/Rupture Study 3.4.1 Tes t C o n d i t i o n s The l o n g t e r m l o a d s t u d y was c o n d u c t e d i n a modern 15,000 s q u a r e f e e t warehouse s t r u c t u r e l o c a t e d i n Burnaby, B.C. which s u b j e c t e d t h e t e s t beams t o an u n c o n t r o l l e d i n t e r i o r e n v i r o n m e n t . The w a r e h o u s e space was h e a t e d w i t h two g a s - f i r e d h e a t e r s w h i c h ma i n t a i n e d a minimum 16°C temperature. Otherwise, the b u i l d i n g was a l l o w e d t o assume ambient temperature and r e l a t i v e h u m i d i t y c o n d i t i o n s d i c t a t e d by the o u t s i d e environment. Temperature and r e l a t i v e humidity records were taken i n t h e w a r e h o u s e by means of a F o x b o r o c o m b i n a t i o n temperature and r e l a t i v e humidity r e c o r d e r . A constant l o a d t e s t method was adopted f o r studying the lo n g term c r e e p / r u p t u r e behaviour of the D o u g l a s - f i r and Parallam beams. Three d i f f e r e n t l o a ds or s t r e s s l e v e l s were used t o d e t e r m i n e the e f f e c t of s t r e s s l e v e l on the 3.4.2 T e s t Method 24 c r e e p / d u r a t i o n o f l o a d r e s p o n s e . The t h r e e n o m i n a l s t r e s s l e v e l s c h o s e n f o r the D o u g l a s - f i r and P a r a l l a m t e s t g r o u p s r e p r e s e n t s t r e s s l e v e l s t h a t a r e 25% f 41% and 56% above t h e i r r e s p e c t i v e a l l o w a b l e design s t r e s s e s . 3.4.3 T e s t Apparatus The constant l o a d was a p p l i e d to each t e s t beam by means of a moment arm l o a d t e s t j i g ( F i g u r e 10). L o a d i n g was a p p r o x i m a t e l y t h i r d p o i n t w i t h a s h e a r - f r e e span r e g i o n of 24 i n c h e s . T e s t beams were p o s i t i o n e d on edge i n t h e moment arm l o a d t e s t and were s u p p o r t e d by m e t a l b e a r i n g p l a t e s ( 3 n x 3 n x l / 8 n ) t o prevent damage to the beams a t the p o i n t of c o n t a c t between the beam and r e a c t i o n s u p p o r t s or l o a d p o i n t s . The t o t a l a p p l i e d l o a d was a combination of the a p p l i e d l o a d package and w e i g h t of the moment arm i t s e l f . The l o a d c o n t r i b u t i o n from the moment arm was determined by an e q u i v a l e n t weight method. T h i s was accomplished by suspending the f r e e end of each moment arm from a 5001b. c a p a c i t y l o a d c e l l . Three d i f f e r e n t moment arm c o n s t r u c t i o n s used i n the study y i e l d e d e q u i v a l e n t dead l o a d s of 22.0 l b . , 23.7 l b . , and 27.0 l b . , r e s p e c t i v e l y . 25 The a p p l i e d l o a d was a l o a d package suspended from each moment arm and was c o m p r i s e d o f a 100 l b l e a d i n g o t and/or a g i v e n w e i g h t of c o n c r e t e b l o c k s . Use of t h e moment arm a l l o w s f o r a s u b s t a n t i a l r e d u c t i o n i n t h e l o a d package weight r e q u i r e d to s t r e s s the t e s t beam to th e r e q u i r e d s t r e s s l e v e l . The l o a d n e c e s s a r y t o produce t h e r e q u i r e d s t r e s s l e v e l was c a l c u l a t e d f o r each i n d i v i d u a l t e s t beam based on the beam's dimensions f o l l o w i n g c o n d i t i o n i n g . The formula used to c a l c u l a t e the r e q u i r e d l o a d package weight i s giv e n below: 1 P = o x S - AWT (3.1) a P = l o a d package weight (lb) a = a p p l i e d s t r e s s (psi) S = s e c t i o n modulus (cu.in.) a = moment arm l e n g t h with a loaded beam (in.) AWT = moment arm e q u i v a l e n t weight (lb) 3.4.4 ' Tes t Layout W i t h 34 r e p l i c a t i o n s f o r each t e s t m a t e r i a l i n each of t h r e e s t r e s s l e v e l s , a t o t a l o f 306 c e s t j i g s a r e r e q u i r e d (3x3x34). The arrangement of the 306 t e s t j i g s i n the Dashv^oa Warehouse i s shown i n F i g u r e 11. The arr a n g e m e n t was such t h a t each t e s t m a t e r i a l g r o u p i n 1 The weight of each l o a d package was a c c u r a t e to ± 0.2 l b . and each moment arm to ±0.1 l b . with a r e s u l t i n g e r r o r i n the a p p l i e d s t r e s s of ± 1% f o r t h e l o w e s t s t r e s s l e v e l . 26 each s t r e s s l e v e l was e q u a l l y d i s t r i b u t e d throughout the warehouse area. 3.4.5 Deformation Measurement The beam def o r m a t i o n recorded was the d e f l e c t i o n i n the s h e a r f r e e span r e g i o n of the beam. D e f l e c t i o n was measured t o the nearest ± 0.001 inch over a 20 i n . l e n g t h by means of a d i a l gauge on a t r i p o d mount. T h i s r e s u l t e d i n measurement e r r o r s r a n g i n g from 1.5-4.0% of of the i n i t i a l d e f l e c t i o n measurement recorded d u r i n g loadup. These d e f l e c t i o n measurements were used i n the c a l c u l a t i o n s of f r a c t i o n a l creep and the s h e a r - f r e e modulus of e l a s t i c i t y (MOEt). 3.4.6 T e s t Procedure The t e s t beams were p l a c e d on t h e i r d e s i g n a t e d t e s t j i g s s uch t h a t the edge l o a d e d i n t e n s i o n d u r i n g p o p u l a t i o n d i v i s i o n work would be l o a d e d i n t e n s i o n d u r i n g l o n g t e r m l o a d i n g . A base or z e r o r e f e r e n c e d e f l e c t i o n r e a d i n g was taken f o r t e s t beam p r i o r to loadup. During loadup, the moment arm and l o a d packages f o r each moment arm l o a d were si m u l t a n e o u s l y placed on t h e t e s t beam i n s u c c e s s i o n a n d t h e t i m e o f l o a d u p f o r e a c h beam recorded. There was approximately a one-minute i n t e r v a l between loadup of s u c c e s s i v e beams. The t e s t commenced with the f i r s t d e f l e c t i o n r e a d i n g taken one minute (0.017 hr) a f t e r the l o a d was a p p l i e d . 27 Ten a d d i t i o n a l d e f l e c t i o n readings were recorded a t the times : 28, 100, 288, 529, 1200, 2325, 3662, 5568, 7416 and 11210 hours. The t e s t f a c i l i t y was checked f o r beam f a i l u r e s on a d a i l y b a s i s f o r the f i r s t three weeks and t h e r e a f t e r on a weekly b a s i s . When a t e s t beam f a i l u r e was observed, the f o l l o w i n g data was recorded: - t e s t beam number f a i l u r e time (day and time the f a i l u r e was noted) t e s t beam weight t e s t beam moisture content A l l three s t r e s s l e v e l s f o r the 1650F D o u g l a s - f i r , 2400F D o u g l a s - f i r and Parallam PSL were loaded on A p r i l 12, 1984. The t e s t was d i s c o n t i n u e d on J u l y 25, 1985 r e s u l t i n g i n a d u r a t i o n of l o a d p e r i o d of 15 months and 13 days. The s u r v i v i n g t e s t beams were p l a c e d i n e. 65% RH, 21°C humid i t y room and c o n d i t i o n e d to constant weight p r i o r to d e s t r u c t i v e f l e x u r e t e s t s . 28 CHAPTER FOUR ANALYSIS OF TEST RESULTS This chapter summarizes the t e s t r e s u l t s o b t a i n e d i n t h i s s t u d y and p r o v i d e s an i n t e r p r e t a t i o n of the r e s u l t s . A n a l y s i s of the creep/rupture performance i s g i v e n i n Chapter 5. 4.1 Short Term F l e x u r e R e s u l t s The s h o r t term f l e x u r e r e s u l t s (t=5 minutes) fo r the three t e s t groups are summarized i n Table 3A w i t h the average moisture content and s p e c i f i c g r a v i t y at time of t e s t . A normal d i s t r i b u t i o n i s assumed f o r these summary r e s u l t s f o r comparison purposes only. The i n d i v i d u a l f l e x u r e r e s u l t s were a d j u s t e d to a common moisture content of 12% i n accordance with procedures recommended i n ASTM D2915 f o r adjustment of lumber property data (11) . P r i o r to f i t t i n g the s t a t i s t i c a l d i s t r i b u t i o n s , the modulus of rupture, p r o p o r t i o n a l l i m i t s t r e s s ( o p l ) a n d modulus of e l a s t i c i t y v a l u e s were a d j u s t e d to 12% moisture content using the f o l l o w i n g e q u a t i o n (ASTM D2915) : P 2 = P i ^fi(MC2>]___ ( 4 > 1 ) [ a-0(MCi) 1 where P 2, P i s t r e n g t h or s t i f f n e s s v a l u e s a t moisture contents MCi and MC 2 r e s p e c t i v e l y , 29 MC2/ M C i = moisture contents,(%) a = 1.75 f o r MOR, o p l a n d 1.44 f o r MOE 3 = 0.0333 f o r MOR, a p l and 0.020 f o r MOE These moisture adjustment equations are recommended f o r a d j u s t i n g s t r e n g t h p r o p e r t i e s of s t r u c t u r a l lumber and have not been s p e c i f i c a l l y v e r i f i e d f o r Parallam. However, the adjustments a p p l i e d to the data r e p o r t e d i n t h i s study are small and approximately the same f o r a l l three t e s t groups. Therefore, a d o p t i o n of these procedures f o r a d j u s t i n g the data to a common base f o r subsequent comparisons i s not expected t o i n t r o d u c e any s i g n i f i c a n t b i a s . The moisture a d j u s t e d summary f l e x u r e r e s u l t s are summarized i n Table 3B. Normal, 2-parameter and 3-parameter W e i b u l l s t a t i s t i c a l d i s t r i b u t i o n s were f i t t e d t o the f l e x u r e r e s u l t s u sing a computer program developed by F o r i n t e k Canada Corp. The degree of f i t of each s t a t i s t i c a l d i s t r i b u t i o n t o the ranked MOR and MOEa r e s u l t s can be seen i n the cumulative frequency p l o t s (cdf) i n F i g u r e s 12 t o 17. A v i s u a l i n s p e c t i o n of the p l o t s shows t h e 3-parameter We i b u l l d i s t r i b u t i o n p r o v i d e s the best f i t t o the experimental data. T h i s i s not s u r p r i s i n g s i n c e the 3-parameter model, w i t h a non-zero l o c a t i o n parameter, w i l l g e n e r a l l y provide improved f i t s t o data when compared to two parameter d i s t r i b u t i o n f u n c t i o n s . Since the W e i b u l l d i s t r i b u t i o n i s the a s y m t o t i c d i s t r i -30 b u t i o n of minimum v a l u e s , there i s a t h e o r e t i c a l b a s i s f o r adopting the W e i b u l l model f o r r e p r e s e n t i n g s t r e n g t h property data. MOE v a l u e s tend to be normally d i s t r i b u t e d . The normal d i s t r i b u t i o n was judged as the next best f i t over the 2-parameter W e i b u l l p a r t i c u l a r l y i n f i t t i n g the lower t a i l of the MOE d i s t r i b u t i o n s . L i n e a r r e g r e s s i o n of MOR on apparent MOE i s i l l u s t r a t e d i n F i g u r e s 18-20 f o r the t h r e e t e s t groups. The c o r r e l a t i o n c o e f f i c i e n t s (r) are s i m i l a r t o each other and compare c l o s e l y to the value of 0.65 r e p o r t e d by G a l l i g a n (12) f o r machine s t r e s s r a t e d lumber. One might expect a b e t t e r c o r r e l a t i o n between MOR and MOE f o r the Parallam g i v e n the homogenous nature of the product, but t h i s was not observed over the range of v a l u e s i n which the r e g r e s s i o n was e v a l u a t e d . 4.2 Creep/Rupture Study 4.2.1 T e s t Environment The creep/rupture study was conducted i n an u n c o n t r o l l e d i n t e r i o r warehouse environment. The temperature and r e l a t i v e humidity (RH) c h a r t s c o l l e c t e d d u r i n g t h e t e s t d u r a t i o n , showed the d a i l y average temperature and percentage r e l a t i v e humidity and c o r r e s p o n d i n g minimum and maximum v a l u e s as f o l l o w s : 31 Temperature (°C) R e l a t i v e Humidity (%) Average 18 58 Maximum 26 74 Minimum 13 41 R e l a t i v e humidity and temperature data were used to c a l c u l a t e corresponding e q u i l i b r i u m moisture contents (EMC) observed a t the t e s t s i t e (13). The c a l c u l a t e d EMC v a l u e s observed are shown i n F i g u r e 21 and i l l u s t r a t e both the wide day-to-day v a r i a t i o n and the seasonal c y c l i c a l t r e n d t o h i g h EMC v a l u e s d u r i n g the summer months f o l l o w e d by lower EMC d u r i n g the winter months. The average EMC observed d u r i n g the 15-1/2 month t e s t d u r a t i o n was 10.7%. Unloaded sample t e s t beams p l a c e d throughout the warehouse were used t o determine average specimen moisture content changes as shown i n F i g u r e 22. Each data p o i n t f o r each t e s t s p e c i e s i s an average of three i n d i v i d u a l r e s u l t s and i s c o n s i d e r e d r e p r e s e n t a t i v e of the e f f e c t of the warehouse environmental c o n d i t i o n s on the loaded t e s t beams. The f i g u r e demonstrates the f o l l o w i n g p o i n t s : The D o u g l a s - f i r t e s t beams e q u i l i b r a t e d t o an average 10.6% moisture content which agrees w e l l with the d e r i v e d v a l u e of 10.7% o b t a i n e d from the Wood Handbook (13) u s i n g the average warehouse temperature and r e l a t i v e humidity c o n d i t i o n s . 32 The Parallam t e s t beams e q u i l i b r a t e d to a lower MC t h a n t h e D o u g l a s - f i r t e s t beams. T h i s can be c h a r a c t e r i s t i c of r e c o n s t i t u t e d wood p r o d u c t s i n g e n e r a l , however, t h i s was not o b s e r v e d f o r the P a r a l l a m f l e x u r e t e s t groups ( s h o r t term and DOL s u r v i v o r s ) which e q u i l i b r a t e d t o t h e same EMC v a l u e s as the D o u g l a s - f i r t e s t groups ( T a b l e s 3A and 4A). T h i s suggests t h a t the t h r e e unstressed Parallam t e s t p i e c e s may not have been r e p r e s e n -t a t i v e of the e n t i r e t e s t p o p u l a t i o n and perhaps, a l a r g e r sample of specimens should be used to monitor moisture content changes. A l l t e s t groups e x h i b i t e d the same t r e n d i n response to the environmental c o n d i t i o n s . Each group e q u i l i b r a t e d to the warehouse EMC d u r i n g the f i r s t t h r e e weeks of the t e s t and subsequent changes were smaller and i n response to the seasonal change i n warehouse EMC. T h i s i s the type of behaviour expected f o r s t r u c t u r a l s i z e lumber members where the member c r o s s - s e c t i o n i s l a r g e enough so t h a t only the outer s u r f a c e s of the member can respond to the d a i l y changes i n temperature and r e l a t i v e humidity. Though the changes i n moisture content observed w i l l a f f e c t the rate of creep, t h i s type of environment sim u l a t e s dry-use s e r v i c e c o n d i t i o n s where some 33 changes to the m a t e r i a l moisture content and dimensions can be expected. T h i s allowed f o r a more p r a c t i c a l comparison of the cree p / r u p t u r e response of the Parallam compared t o the s o l i d sawn D o u g l a s - f i r groups. To conduct a study of t h i s s i z e i n a c o n t r o l l e d , constant temperature and humidity environment i s i m p r a c t i c a l because of space and time requirements and the need t o r e l a t e the r e s u l t s t o a c t u a l environments. 4.2.2 I n i t i a l Deformation and Modulus of E l a s t i c i t y As d e s c r i b e d i n t h e p r e v i o u s c h a p t e r , t h e d e f o r m a t i o n measurement was recorded i n the s h e a r - f r e e r e g i o n of the beam over a 20-inch chord l e n g t h . The advantage of t h i s a p p r o a c h i s t h a t t h e m o d u l u s of e l a s t i c i t y v a l u e c a l c u l a t e d i s the s h e a r - f r e e or pure bending MOE which u n l i k e a p p a r e n t MOE i s not dependent on t h e l o a d i n g arrangement of the beam. In t h i s study, the i n i t i a l modulus of e l a s t i c i t y v a l u e s (MOEt) f o r each beam was was c a l c u l a t e d from the one minute d e f o r m a t i o n value (60). The i n d i v i d u a l s h e a r - f r e e modulus of e l a s t i c i t y v a l u e s (t=l minute) f o r each t e s t beam are summarized i n Appendix I I . I n s p e c t i o n of the s h e a r - f r e e modulus of e l a s t i c i t y v a l u e s f o r each t e s t group shows t h a t the matching of the s t r e s s l e v e l groups was maintained though the i n d i v i d u a l ranking of beams was a l t e r e d . L i n e a r r e g r e s s i o n a n a l y s i s between the MOEt v a l u e s f o r the 34 three s t r e s s l e v e l s f o r each t e s t group and the MOEa val u e s from the p o p u l a t i o n d i v i s i o n work i s shown i n Figu r e 23. A high degree of c o r r e l a t i o n between the MOEt and MOEa v a l u e s was confirmed by the c o r r e l a t i o n (r) of 0.87, 0.86 and 0.90 f o r t h e 1650F D o u g l a s - f i r , 2400F D o u g l a s - f i r and P a r a l l a m t e s t groups, r e s p e c t i v e l y . 4.2.3 Creep (Deformation) Study R e s u l t s The c r e e p r e s u l t s o b s e r v e d i n t h i s s t u d y have been summarized i n t h e f o r m of d e f l e c t i o n and f r a c t i o n a l creep data i n the f o l l o w i n g ways f o r the th r e e r e s p e c t i v e s t r e s s l e v e l s : 1. P l o t s of i n d i v i d u a l d e f l e c t i o n r e s u l t s versus time i n F i g u r e s 24-32 and p l o t s of i n d i v i d u a l f r a c t i o n a l creep r e s u l t s v e r s u s time i n Fi g u r e s 33-41. 2. P l o t s of average d e f l e c t i o n v ersus normal time i n F i g u r e 42 and average d e f l e c t i o n v e r s u s l o g time i n F i g u r e 43. A l s o , average d e f l e c t i o n v e rsus time i n t a b u l a r form i n T a b l e s 5A-5C. 3. P l o t s of average f r a c t i o n a l c r e e p v s . normal t i m e i n F i g u r e s 44-46 and average f r a c t i o n a l creep vs. l o g time i n F i g u r e s .47-49. A l s o average f r a c t i o n a l creep v e r s u s time i n t a b u l a r form i n Tables 5A-5C. 35 4. Summaries of the i n d i v i d u a l d e f l e c t i o n and i n d i v i d u a l f r a c t i o n a l creep r e s u l t s i n t a b u l a r form i n Appendix I I I . A number of general comments can be made about the creep curves o b t a i n e d : 1. The c r e e p c u r v e s show c h a r a c t e r i s t i c p r i m a r y and se c o n d a r y c r e e p b e h a v i o u r f o r t h e t h r e e s t r e s s l e v e l s i n t h i s s t u d y a f t e r 15-1/2 months l o a d d u r a t i o n . The Parallam creep curves e x h i b i t e d the same general c h a r a c t e r i s t i c s as the two s o l i d wood D o u g l a s - f i r creep curves. 2. The m a j o r i t y of the beam f a i l u r e s o c c u r r e d d u r i n g t h e p r i m a r y c r e e p s t a g e w h e r e t h e r a t e of deformation i s d e c r e a s i n g d u r i n g the i n i t i a l s t r e s s s t a b i l i z a t i o n p e r i o d . Creep curves f o r beams that f a i l e d are shown up to the time of f a i l u r e and then as s t r a i g h t l i n e s down to zero d e f l e c t i o n . 3. The f o u r t h set of d e f l e c t i o n measurements (t=529 hr) f o r many of the creep curves appears anomalous with respect to the r e s t of the measurements. T h i s can be seen i n the i n d i v i d u a l creep curves (Figures 24-32) and average creep curves ( F i g u r e s 42,43) as an abrupt l e v e l l i n g o f f of the cu r v e s . The reason f o r t h i s i s not c l e a r and may be due to a systematic e r r o r i n the d e f l e c t i o n measurements f o r t h i s time 36 p e r i o d . Another p o s s i b l e e x p l a n a t i o n i s an i n c r e a s e i n the creep r a t e as the t e s t beams e q u i l i b r a t e d to the warehouse e q u i l i b r i u m moisture content. A change i n beam moisture content was observed during the f i r s t t h r e e weeks ( %500 hr) of the t e s t (see Fi g u r e 22). Both Hoyle et a l (14) and Armstrong and C h r i s t e n s e n (15) observed i n c r e a s e d creep during d e s o r p t i o n i n c y c l i c humidity bending creep t e s t s w i t h wood. F u r t h e r a n a l y s i s o f t h e c r e e p r e s u l t s i s l e f t to t h e d i s c u s s i o n and t e c h n i c a l a n a l y s i s s e c t i o n i n the n e x t chapter. A f t e r 15-1/2 months o f l o a d d u r a t i o n , a t o t a l of 16 beam f a i l u r e s were observed as f o l l o w s : 4.2.4 Rupture ( F a i l u r e ) Study R e s u l t s T e s t Group S t r e s s L e v e l 1 S t r e s s L e v e l 2 S t r e s s L e v e l 3 1650F D o u g l a s - f i r 0 of 34 1 of 34 4 of 34 2400F D o u g l a s - f i r 1 of 3 4 5 of 3 4 4 of 3 4 Parallam PSL 1 of 34 0 of 34 0 of 34 zero f a i l u r e s of 34 beams i n i t i a l l y loaded. F o u r t e e n of t h e 15 D o u g l a s - f i r f a i l u r e s i n i t i a t e d a t k n o t s l o c a t e d on or near t h e t e n s i o n edge of the beam. 37 F a i l u r e o c c u r r e d when the c r a c k p r o p a g a t e d a l o n g t h e g r a i n u n t i l i t reached e i t h e r another knot or u n t i l the net c r o s s - s e c t i o n of t h e wood was r e d u c e d t o the p o i n t w h e r e i t c o u l d no l o n g e r s u s t a i n t h e l o a d . The r e m a i n i n g D o u g l a s - f i r f a i l u r e was a s l o p e of g r a i n f a i l u r e . The s i n g l e P a r a l l a m t e s t beam f a i l u r e ex-h i b i t e d i n i t i a l l y , a p a r t i a l d e l a m i n a t i o n approximately one i n c h i n from the t e n s i o n edge which was f i r s t ob-s e r v e d a p p r o x i m a t e l y 3000 h o u r s i n t o the t e s t . The del a m i n a t i o n slowly propagated along the l o n g i t u d i n a l s t r a n d o r i e n t a t i o n u n t i l t o t a l f a i l u r e o c c u r r e d a t 10,960 hours. Time to f a i l u r e ( s u r v i v a l ) r e s u l t s f o r the th r e e t e s t groups are shown i n F i g u r e s 50-52 and i n Table 6. In a d d i t i o n t o the above f a i l u r e s , a number of t e s t beams e x h i b i t e d p a r t i a l f a i l u r e s where cracks were observed ( u s u a l l y around knots) but the member s t i l l maintained the a p p l i e d load. The number of t e s t beams observed to e x h i b i t p a r t i a l f a i l u r e s y e t s u r v i v e d the t e s t p e r i o d are summarized below: Number of P a r t i a l F a i l u r e s T e s t Group S t r e s s L e v e l 1 S t r e s s L e v e l 2 S t r e s s L e v e l 3 1650F D o u g l a s - f i r 3 of 3 4 1 3 of 3 4 4 of 3 4 2400F D o u g l a s - f i r 1 of 3 4 3 of 34 2 of 34 Parallam PSL 0 of 3 4 0 of 3 4 0 of 3 4 1 3 f a i l u r e s o f 34 beams i n i t i a l l y l o a ded. 38 Flexure t e s t r e s u l t s f o r the s u r v i v i n g t e s t beams from the c r e e p / r u p t u r e study a r e summarized i n Table4A f o r moisture content a t t e s t and i n Table 4B w i t h the r e s u l t s a d j u s t e d t o 12% moisture content. A number of comments r e g a r d i n g the t e s t r e s u l t s o b t a i n e d f o r the s u r v i v o r s can be made: a l l three t e s t groups e q u i l i b r a t e d t o approximately the same EMC (11.5-11.7% MC) a f t e r r e - c o n d i t i o n i n g i n a 65% RH 21°C environment. The adjustment t o 12% MC was made f o r comparison to the short term f l e x u r e r e s u l t s and the adjustment appears v a l i d f o r the same reasons s t a t e d f o r the short term f l e x u r e r e s u l t s . A one-way a n a l y s i s of v a r i a n c e (ANOVA) of t h e modulus of r u p t u r e r e s u l t s showed no s t a t i s t i c a l d i f f e r e n c e between the th r e e s t r e s s l e v e l s of each t e s t m a t e r i a l a t the 0.05 l e v e l of s i g n i f i c a n c e ( c r i t i c a l F=3.11 > 0.79, 0.16 and 0.73 f o r the 1650F D o u g l a s - f i r , 2400F D o u g l a s - f i r and Pa r a l l a m r e s p e c t i v e l y ) . T h i s r e s u l t i n d i c a t e s t h a t the pop-u l a t i o n d i v i s i o n procedure was e f f e c t i v e i n match-i n g the s t r e n g t h d i s t r i b u t i o n s . The r e s u l t s of the s t a t i s t i c a l a n a l y s i s are summarized i n Appendix I. The t e s t beams e x h i b i t i n g p a r t i a l f a i l u r e s d i d not n e c e s s a r i l y g i v e the lowest MOR or MOEa v a l u e s 39 though a l l were s i t u a t e d towards the low end of the s t r e n g t h or s t i f f n e s s d i s t r i b u t i o n . These r e s u l t s have been i n c l u d e d i n the summary f l e x u r e r e s u l t s f o r the DOL s u r v i v o r s . F u r t h e r a n a l y s i s of the ru p t u r e r e s u l t s i s l e f t to the D i s c u s s i o n and T e c h n i c a l A n a l y s i s S e c t i o n i n the next chapter. 40 CHAPTER FIVE DISCUSSION AND TECHNICAL ANALYSIS 5.1 Rupture Results 5.1.1 Overview The t h r e e s t r e s s l e v e l s chosen f o r t h i s study were 25%, 41% and 56% gr e a t e r than the corresponding a l l o w a b l e design s t r e s s e s of the three t e s t groups a p p l i c a b l e to nominal 2x4 t e s t specimen c r o s s - s e c t i o n s . I t i s i n s t r u c t i v e to compare the range of s t r e s s r a t i o s s t u d i e d . The s t r e s s r a t i o i s d e f i n e d as the r a t i o of the a p p l i e d s t r e s s t o s h o r t term u l t i m a t e f l e x u r e s t r e n g t h and was c a l c u l a t e d using the moisture a d j u s t e d s h o r t -term f l e x u r e s t r e n g t h r e s u l t s of the c o n t r o l samples. A summary of the average, minimum and maximum s t r e n g t h r a t i o s f o r each t e s t group and s t r e s s l e v e l i s giv e n below : Stress Ratio r o/MOR, (%) 1650F 2400F Douglas-fir Douglas-fir Parallam PSL S t r e s s L e v e l 1 Average Range 2 9 . 8 1 7 - 6 0 3 2.8 21-93 39.9 30-55 S t r e s s L e v e l 2 Average Range 3 3 . 6 1 9 - 6 8 36.9 24-105 44.8 33-61 S t r e s s L e v e l 3 Average 37.2 41.0 49.8 Range 21-75 27-117 37-68 41 The s t r e s s r a t i o v a l u e s show t h a t even though t h e three t e s t m a t e r i a l s are s t r e s s e d t o the same m u l t i p l e of t h e i r a l l o w a b l e design s t r e s s , they are not s t r e s s e d t o t h e same f r a c t i o n of t h e i r s h o r t - t e r m s t r e n g t h . T h i s , of c o u r s e , i s n o t a s u r p r i s i n g r e s u l t . I f t h e sample p o p u l a t i o n s a re a good d e s c r i p t i o n of t h e i r true p o p u l a t i o n s , t h e n each would be s t r e s s e d t o the same m u l t i p l e of t h e i r 5 per cent e x c l u s i o n l i m i t s . The much t i g h t e r c o e f f i c i e n t of v a r i a t i o n (CV) f o r the Par a l l a m g roup ( i n p a r t which j u s t i f i e s t h e h i g h e r P a r a l l a m a l l o w a b l e bending s t r e s s ) r e s u l t s i n the Par a l l a m group b e i n g s t r e s s e d t o a h i g h e r p e r c e n t a g e of i t s mean s t r e n g t h . In the case of the two D o u g l a s - f i r g r o u p s , t h e f a c t t h a t they a r e c l o s e to b e i n g e q u a l l y s t r e s s e d i n d i c a t e s t h a t t h e i r s t r e n g t h d i s t r i b u t i o n s have s i m i l a r CVs. The t a b l e demonstrates how sm a l l the d i f f e r e n c e i n av e r a g e s t r e s s r a t i o s i s between the a p p l i e d s t r e s s l e v e l s , f o r each t e s t group. From a p r a c t i c a l p o i n t of view, the a p p l i e d s t r e s s l e v e l s are u s e f u l i n e v a l u a t i n g c r e e p b e h a v i o u r a t l o a d l e v e l s e x p e c t e d i n s e r v i c e , h o w e v e r , i t makes e v a l u a t i o n of d u r a t i o n o f l o a d behaviour more d i f f i c u l t . I t was r e c o g n i z e d a t the b e g i n n i n g of the study t h a t t h e s a m p l e s i z e a nd s t r e s s l e v e l s c h o s e n w o u l d make i n t e r p r e t a t i o n of the d u r a t i o n of l o a d e f f e c t d i f f i c u l t . 42 N o n e t h e l e s s , an a n a l y s i s i s p r e s e n t e d h e r e t o d e m o n s t r a t e some of t h e t e c h n i q u e s a v a i l a b l e f o r a n a l y z i n g DOL data and i d e n t i f y i n g the shortcomings of these techniques with respect to the ex p e r i m e n t a l design of t h i s study. 5.1.2 A n a l y s i s Methods A number of methods are a v a i l a b l e f o r a n a l y z i n g the data f r o m t i m e - s t r e n g t h r e l a t i o n s h i p e x p e r i m e n t s . Four d i f f e r e n t methods used by Madsen and B a r r e t t (3) i n c l u d e : a. Number of s u r v i v i n g s p e c i m e n s as a p e r c e n t a g e of the t o t a l sample. b. Number of s u r v i v i n g s p e c i m e n s as a p e r c e n t a g e of the number of s p e c i m e n s s t r o n g e r t h a n t h e a p p l i e d s t r e s s l e v e l . c. A p p l i e d s t r e s s r a t i o using the c o n t r o l sample. d. A p p l i e d s t r e s s r a t i o using the t e s t data. In t h i s s tudy, method (a) and (b) a r e e s s e n t i a l l y t h e same s i n c e no f a i l u r e s o c c u r r e d on l o a d i n g . Method (c) i s t h e t r a d i t i o n a l approach where c o m p a r i s o n t o t h e Madison d u r a t i o n of l o a d curve can be made. Method (d) i s the one p r e f e r r e d by Madsen and B a r r e t t i n t h e i r 43 analysis of the time-strength behaviour of s t r u c t u r a l size lumber (3). Methods (a), (c) and (d) were used to obtain an impression of the time-strength r e l a t i o n s h i p for the three test groups i n t h i s study. 5.1.3 S u r v i v a l P r o b a b i l i t i e s The number of surviving specimens as a percentage of the t o t a l sample i s p l o t t e d a g a i n s t time on a l o g s c a l e i n Figures 50-52 for the 1650F, 2400F Douglas-fir and Parallam test groups, respectively. Curves have been drawn through the data points to i l l u s t r a t e the trend. The data has also been tabulated i n Table 6. No trend can be i l l u s t r a t e d for the Parallam and the lower stress l e v e l s for the Douglas-fir groups due to the absence of f a i l u r e s . The expected trend showing a decrease i n s u r v i v a l percentage with i n c r e a s e d a p p l i e d s t r e s s was observed f o r the 1650F D o u g l a s - f i r group but not the 2400F D o u g l a s - f i r group. However, the d i f f e r e n c e i n the number of f a i l u r e s between the two higher stress l e v e l s for the 2400F Douglas-fir (5 versus 4 f a i l u r e s ) i s small and not s t a t i s t i c a l l y s i g n i f i c a n t . Too few f a i l u r e s were observed to make any r e a l i s t i c comparison of the survival curves between the test groups. Further analysis of the survival p r o b a b i l i t i e s of the 44 three t e s t m a t e r i a l s can be made by comparing the ob-served number of f a i l u r e s w i t h the number of f a i l u r e s p r e d i c t e d by v a r i o u s d u r a t i o n of l o a d models. F i g u r e 4 shows th r e e such DOL models: the Madison ' h y p e r b o l i c ' curve, the Madison l i n e a r t r e n d l i n e from constant l o a d t e s t s on s m a l l , c l e a r specimens(2) and the 'hemlock lumber' curve o b t a i n e d by Fosc h i and B a r r e t t (4). The p r e d i c t e d number of f a i l u r e s a re those whose s t r e n g t h as determined from the short term s t r e n g t h d i s t r i b u t i o n i s below the s t r e s s v a l u e , o*fdetermined by d i v i d i n g the a p p l i e d s t r e s s (o ) by a s t r e s s r a t i o d e r i v e d from the d u r a t i o n of l o a d curve ( o / S R ) . If we examine the Madison 'hyperbolic* curve a t t=11210 hours, the mean s t r e s s r a t i o i s approximately 0.67. A c c o r d i n g l y , t h e high s t r e s s l e v e l 2400F D o u g l a s - f i r t e s t group ( a=3750 p s i ) , specimens w i t h a short-term s t r e n g t h below 5600 p s i ( i e 3750/0.67) would be expected t o f a i l i n 11210 hours. For the 'hemlock lumber' curve the number of f a i l u r e s expected a t 11,210 hours was determined by computer s i m u l a t i o n . The model parameters d e r i v e d from the hem-l o c k lumber study were a d j u s t e d t o r e f l e c t the v a r i -a b i l i t y i n short-term s t r e n g t h observed f o r the Douglas - f i r lumber and Parallam t e s t e d i n t h i s study. By repea t i n g the s i m u l a t i o n 10 times, a range of expected number of f a i l u r e s can be determined. A comparison of the observed and p r e d i c t e d number of f a i l u r e s as d e t e r -mined from the Madison 'hyperbolic' curve and l i n e a r 45 t r e n d l i n e and from the 10 s i m u l a t i o n s w i t h the 'hemlock lumber' curve i s given below: Test Stress Number of F a i l u r e s Predicted 1 No. of Group Level Madison 'Hemlock Observed (psi) 'Hyperbolic' Linear Lumber' Failures Curve Trend Line Curve 1650F 2060 0 0 0 - 2 0 Douglas-fir 2325 0 - 1 0 - 1 1 - 5 1 2575 0 - 1 1 - 2 1 - 5 4 2400F 3000 1 1 - 2 0 - 3 1 Douglas-fir 3375 1 - 2 1 - 2 1 - 5 5 3750 2 - 3 3 1 - 5 4 Parallam 4000 0 0 0 - 1 1 PSL 4500 0 0 - 1 1 - 5 0 5000 0 - 1 1 - 2 1 - 6 0 1 t = 11210 hr. The t a b l e shows t h a t the number of observed f a i l u r e s f o r the D o u g l a s - f i r m a t e r i a l i s w i t h i n the range of p r e d i c t e d f a i l u r e s determined from the 'hemlock lumber' curve and equal t o or greater than the p r e d i c t e d number of f a i l u r e s determined from the Madison ' h y p e r b o l i c * curve or l i n e a r t r e n d l i n e . The observed number of f a i l u r e s f o r the Parallam m a t e r i a l was c o n s i s t e n t w i t h those p r e d i c t e d from the Madison 'hyperbolic' curve or l i n e a r t r e n d l i n e and l e s s than those p r e d i c t e d from the 'hemlock lumber' curve. These r e s u l t s suggest t h a t the d u r a t i o n of l o a d behaviour f o r the D o u g l a s - f i r m a t e r i a l i s c o n s i s t e n t with t h a t found f o r s t r u c t u r a l s i z e lumber ('hemlock lumber' curve) whereas the P a r a l l a m i s b e t t e r represented by d u r a t i o n of l o a d behaviour of the Madison ' h y p e r b o l i c ' curve. 46 5.1.4 Applied Stress Ratio Using Control Sample T h i s method of a n a l y s i s assumes t h a t the i n d i v i d u a l t e s t s p e c i m e n s have the same s t r e n g t h d i s t r i b u t i o n as the s h o r t term s t r e n g t h c o n t r o l samples. Then the i n i t i a l s t r e n g t h of the t e s t s p e c i m e n f a i l i n g under l o a d i s assumed to be given by the c o n t r o l t e s t specimen a t the same rank. To v e r i f y the assumption of s i m i l a r d i s t r i -b u tions, cumulative frequency d i s t r i b u t i o n (cdf) of the s u r v i n g DOL t e s t specimens t e s t e d to d e s t r u c t i o n a f t e r d i s c o n t i n u a t i o n of the l o n g term l o a d study were p l o t t e d and the short term s t r e n g t h cdf superimposed on i t . The p l o t s shown i n F i g u r e s 53 - 55 demonstrate the above assumption i s a reasonable one f o r the two D o u g l a s - f i r groups. The agreement i s not as good f o r the Parallam and i s a t t r i b u t e d to too small a sample s i z e f o r the p o p u l a t i o n d i v i s i o n method based on dynamic MOE. Using the 3-parameter W e i b u l l d i s t r i b u t i o n to d e s c r i b e the s h o r t term s t r e n g t h d i s t r i b u t i o n , p l o t s of the e s t i m a t e d a p p l i e d s t r e s s r a t i o s v e r s u s the l o g a r i t h m of the time to f a i l u r e a r e shown i n F i g u r e 56. For comparson purposes, the Madison and 'hemlock lumber* curves are i n c l u d e d , a d j u s t e d t o a 5-minute time to f a i l u r e which was the average time to f a i l u r e f o r the c o n t r o l s . The p l o t shows most of the data p o i n t s to f a l l below both curves, however, because of the s m a l l sample s i z e , a c curate e s t i m a t e s of a p p l i e d s t r e s s r a t i o s 47 are d i f f i c u l t to o b t a i n . With s m a l l sample s i z e s , d i v i d i n g the s h o r t term s t r e n g t h d i s t r i b u t i o n i n i n t e r v a l s i n order t o a s s i g n an e s t i m a t e d short-term s t r e n g t h to specimens which f a i l e d under long term l o a d can produce l a r g e d i f f e r e n c e s between a s s i g n e d s t r e s s r a t i o s . The d i f f i c u l t i e s are i l l u s t r a t e d i n F i g u r e 30 which shows the two beam f a i l u r e s f o r the 2400F Douglas-f i r group s t r e s s e d a t 3375 p s i ( s t r e s s l e v e l 2). The two beam f a i l u r e s , both observed a t 74 hours, have l a r g e d i f f e r e n c e s i n c a l c u l a t e d s t r e s s r a t i o s (78% vs. 65%). I n c r e a s i n g the a p p l i e d s t r e s s l e v e l would produce more beam f a i l u r e s but again, too s m a l l a sample s i z e would make i t d i f f i c u l t t o a c c u r a t e l y e s t i m a t e the t a i l of the s h o r t term s t r e n g t h d i s t r i b u t i o n . No q u a n t i t a t i v e statement about the decay of mechanical s t r e n g t h w i t h time f o r the three t e s t m a t e r i a l s can be made with t h i s method of a n a l y s i s f o r the reasons s t a t e d above. 5.1.5 A p p l i e d S t r e s s R a t i o U s i n g T e s t Data T h i s method of a n a l y s i s i s the same a s the p r e v i o u s s e c t i o n with the e x c e p t i o n t h a t the cumulative stren g t h d i s t r i b u t i o n s of the s u r v i v i n g long term l o a d t e s t spe-cimens were used r a t h e r t h a t those of the s h o r t term st r e n g t h c o n t r o l specimens. As shown i n f i g u r e s 53 - 55, i t i s necessary to r e c o n s t r u c t the lower t a i l of the c u m u l a t i v e s t r e n g t h d i s t r i b u t i o n s due t o the beam f a i l u r e s which o c c u r r e d d u r i n g t h e study. S i n c e no 48 f a i l u r e s were o b t a i n e d d u r i n g the t e s t l o a d u p , the r e c o n s t r u c t e d lower t a i l was chosen t o go to zero a t the value of the a p p l i e d s t r e s s . Curves were estimated by l i n e a r r e g r e s s i o n a n a l y s i s using the a p p l i e d s t r e s s l e v e l as the minimum s t r e n g t h °o, and the 10 lowest s t r e n g t h v a l u e s from the e x i s t i n g cumulative d i s t r i b u t i o n i n order t o e s t i m a t e the parameters of the f o l l o w i n g e q u a t i o n : Y = a ( a - a 0 ) b (5.1) where Y = cumulative p r o b a b i l i t y o = p r e d i c t e d short term s t r e n g t h o 0 = a p p l i e d s t r e s s l e v e l (minimum strength) a,b = constants determined f o r each d i s t r i b u t i o n The r e c o n s t r u c t e d t a i l s f o r the 3 t e s t groups which ex-h i b i t e d more than one f a i l u r e are shown i n the same f i g u r e s . I n s p e c t i o n shows the r e c o n s t r u c t e d t a i l d i s -t r i b u t i o n s t o be reasonable c o n t i n u a t i o n s of the e x i s t -i n g c urves. P l o t s of e s t i m a t e d a p p l i e d s t r e s s r a t i o versus l o g time using these d i s t r i b u t i o n s are shown i n F i g u r e 57 and i n d i c a t e c l o s e r agreement t o the Madison and 'hemlock lumber' curves than the s t r e s s r a t i o v a l u e s obtained using the s h o r t term s t r e n g t h c o n t r o l d i s t r i b u t i o n s . However, i t i s not p o s s i b l e t o make any q u a n t i t a t i v e statement r e g a r d i n g the decay of mechanical s t r e n g t h 49 w i t h time due t o the few f a i l u r e s observed i n t h i s study. 5.1.7 D i s c u s s i o n The o b j e c t i v e of t h e s e a n a l y s e s was t o e v a l u a t e t h e creep r u p t u r e performance of the Parallam PSL m a t e r i a l a g a i n s t the two MSR D o u g l a s - f i r c o n t r o l groups. Based on the number of beam f a i l u r e s observed, no q u a n t i t a t i v e comparison the DOL performance of the t e s t m a t e r i a l s can be made. Higher a p p l i e d s t r e s s e s and l a r g e r sample s i z e s would permit a b e t t e r e v a l u a t i o n of the creep rupture performance. A computer s i m u l a t i o n study c a r r i e d out by Madsen and Warren (11) i n d i c a t e d t h a t a sample s i z e of 80 commercial D o u g l a s - f i r beams was necessary t o give s u f f i c i e n t confidence that a d i f f e r e n c e i n the number of observed f a i l u r e s was s i g n i f i c a n t . For Parallam with i t s i n h e r e n t lower v a r i a b i l i t y , the sample s i z e would be s l i g h t l y s m a l l e r than 80 to achieve the same l e v e l of confidence (~60) . The a b s e n c e of P a r a l l a m f a i l u r e s f o r the two h i g h e r s t r e s s l e v e l s suggests t h a t the Parallam DOL performance i s no worse than that p r e d i c t e d by the Madison 'hyperbolic'curve up t o 15-1/2 months l o a d d u r a t i o n . The a n a l y s i s f u r t h e r suggests that the Parallam DOL performance i s c o n s i s t e n t with the Madison l i n e a r t r e n d l i n e i n d i c a t i n g s i m i l a r behaviour to c l e a r , s t r a i g h t 50 g r a i n specimens. T h i s i s f u r t h e r supported by the p r o p o r t i o n a l l i m i t v a l u e s obtained from the s h o r t term s t r e n g t h and DOL s u r v i v o r s f l e x u r e t e s t s which averaged 59% and 63%, r e s p e c t i v e l y of t h e i r bending s t r e n g t h v a l u e s . These v a l u e s are c o n s i s t e n t w i t h the value of 9/16 or 0.56 used i n the codes t o reduce s h o r t term s t r e n g t h f o r the e f f e c t s of long term continuous l o a d i n g . The 9/16 value was i n i t i a l l y t he r a t i o of the p r o p o r t i o n a l l i m i t l o a d to u l t i m a t e l o a d e s t a b l i s h e d f o r small c l e a r specimens. The d u r a t i o n of l o a d adjustment f a c t o r s are c u r r e n t l y being r e - e v a l u a t e d f o r commercial s i z e lumber because they do not f o l l o w the Madison curve. Madsen and B a r r e t t (3) found t h a t the present t i m e - s t r e n g t h r e l a t i o n s h i p i s c o n s e r v a t i v e f o r lumber i n bending f o r time p e r i o d s up to one y e a r . I f t h i s i s the case, t h e n one c o u l d argue t h a t t h e c u r r e n t d u r a t i o n of l o a d a d j u s t m e n t f a c t o r s used i n the codes c o u l d be a p p l i e d t o d e v e l o p w o r k i n g s t r e s s e s f o r Parallam. 5.1.7 Summary A n a l y s i s of the creep rupture r e s u l t s of t h i s study f o r the t h r e e t e s t m a t e r i a l s : 1650F,1.5E Douglas-f i r ,240OF, 2.0E D o u g l a s - f i r and Pa r a l l a m a f t e r 15-1/2 months l o a d d u r a t i o n i n d i c a t e t h a t : 1 . No q u a n t i t a t i v e statement on the comparative per-51 formance of the time-strength behaviour between Parallam PSL and the two MSR Douglas-fir materials can be made due to the few f a i l u r e s obtained. The l i m i t e d time-to-failure data suggests that Parallam, under the constant loads studied, w i l l e x h i b i t fewer f a i l u r e s than predicted by the 'hemlock lumber' curve . The time-to-failure data appears more consistent with that predicted by the Madison curve or the l i n e a r trend l i n e through the small, clear specimen data. There re s u l t s suggest that the current duration of load adjustment factors can be applied to Parallam PSL. The l i m i t e d time-to-failure data suggests that the MSR Douglas-fir lumber, under the constant loads studied, w i l l exhibit f a i l u r e s consistent with that predicted by the 'hemlock lumber' curve. 52 5.2 Creep Study 5.2.1 Creep D e f l e c t i o n To c h a r a c t e r i z e t h e c r e e p b e h a v i o u r and compare t h e P a r a l l a m t e s t group t o the MSR D o u g l a s - f i r groups, d e f l e c t i o n v e r s u s time p l o t s were c o n s t r u c t e d f o r the 34 i n d i v i d u a l t e s t beams i n each t e s t group f o r each s t r e s s l e v e l . The p l o t s shown i n F i g u r e s 24 - 32 d e m o n s t r a t e t h e v a r i a b i l i t y i n t o t a l d e f l e c t i o n observed f o r each t e s t group. T h i s observed v a r i a b i l i t y i s , of c o u r s e , f r o m two c o n t r i b u t i o n s - (1) i n i t i a l d e f l e c t i o n v a r i a b i l i t y ( i . e . , d i f f e r e n c e s i n MOE) and (2) creep d e f l e c t i o n v a r i a b i l i t y (i.e., d i f f e r e n t r a t e s of r e s p o n s e t o t h e a p p l i e d s t r e s s ) . The c u r v e s show s i m i l a r v a r i a b i l i t y between t e s t groups w i t h a tendency t o w a r d s g r e a t e r v a r i a b i l i t y a t h i g h e r s t r e s s l e v e l s . The p l o t s a l s o show h i g h e r i n i t i a l d e f l e c t i o n s f o r t h e Parallam t e s t groups. To b e t t e r compare t h e o b s e r v e d beam d e f l e c t i o n s , t h e av e r a g e d e f l e c t i o n f o r each t e s t group and a t each s t r e s s l e v e l was p l o t t e d on the same graph a g a i n s t time on a l i n e a r s c a l e i n Fi g u r e 42 and a g a i n s t time on a l o g a r i t h m i c s c a l e i n F i g u r e 43. These f i g u r e s c o n f i r m the expected t r e n d of higher d e f l e c t i o n a t hig h e r s t r e s s l e v e l s w i t h Parallam showing the l a r g e s t t o t a l d e f l e c t i o n of the t h r e e groups. The d e f l e c t i o n 53 v e r s u s l o g time p l o t demonstrates t h a t the high e r observed d e f l e c t i o n f o r Parallam i s i n p a r t due to hig h e r i n i t i a l d e f l e c t i o n a t load-up. T h i s was expected s i n c e the Parallam t e s t group was loaded t o high e r percentages of i t s short term s t r e n g t h and s t i f f n e s s v a l u e s . The average d e f l e c t i o n versus time observed has a l s o been t a b u l a t e d i n Tables 5A-5C . At the t e s t c o n c l u s i o n (t=ll,210 hr), the average d e f l e c t i o n 6(t) and r a t i o of d e f l e c t i o n t o a p p l i e d s t r e s s ( 6(t)/o) observed f o r each m a t e r i a l was as f o l l o w s : Stress Level 1 Stress Level 2 Stress Level 3 6(t) 6(t)/o 6(t) Sft)/o 6(t) 6Tt)/j 1~3 - i r» \ M n \ l l f l " J i r (in.) (10~ 3 in.) (in.) (10~ 3 iru) (i .) (10~^ in.) p s i p s i p s i 1650F DF Mean 0.054 0.026 0.058 0.025 0.067 0.026 (%cv) (29.2) (18.5) (24.4) 2400F DF Mean 0.058 0.019 0.064 0.019 0.072 0.019 (%cv) (15.8) (16.8) (16.7) Parallam PSL Mean 0.075 0.019 0.084 0.019 0.093 0.019 (%cv) (12.0) (11.2) (12.6) T h i s t a b l e b e t t e r i l l u s t r a t e s t h e v a r i a b i l i t y i n d e f l e c t i o n observed a f t e r 15-1/2 months l o a d d u r a t i o n . The Pa r a l l a m m a t e r i a l e x h i b i t e d the lowest v a r i a b i l i t y o f a l l t h r e e t e s t g r o u p s . The 1650F D o u g l a s - f i r m a t e r i a l showed the g r e a t e s t v a r i a b i l i t y with l a r g e d i f f e r e n c e s i n c o e f f i c i e n t of v a r i a t i o n v a l u e s between the t h r e e s t r e s s l e v e l s due to the presence of a s i n g l e t e s t beam i n s t r e s s l e v e l one and s t r e s s l e v e l t h r e e 54 w h i c h e x h i b i t e d a c o n s i d e r a b l y l a r g e r d e f l e c t i o n t h a n the r e s t of the t e s t beams but had n o t f a i l e d a t t h e time the t e s t was d i s c o n t i n u e d . The r a t i o of d e f l e c t i o n to a p p l i e d s t r e s s i s e s s e n t i a l l y constant over the three s t r e s s l e v e l s f o r each t e s t m a t e r i a l . The lower d e f l e c t i o n to a p p l i e d s t r e s s response f o r the 2400F D o u g l a s - f i r and Parallam m a t e r i a l compared t o the 1650F D o u g l a s - f i r m a t e r i a l i s i n d i c a -t i v e of a higher q u a l i t y wood. 5.2.2 F r a c t i o n a l Creep A c o m p a r i s o n of t h e beam d e f o r m a t i o n due t o c r e e p between the t h r e e t e s t m a t e r i a l s i s p r e s e n t e d i n t h e f o r m of f r a c t i o n a l c r e e p v e r s u s t i m e p l o t s . In t h i s study, f r a c t i o n a l creep i s d e f i n e d as the r a t i o of t o t a l d e f l e c t i o n t o t h e i n i t i a l d e f l e c t i o n ( 6 t / 6 o ) a n d pr o v i d e s a r e l a t i v e measure of creep between m a t e r i a l s . The f r a c t i o n a l c r e e p v e r s u s t i m e p l o t s f o r t h e 34 i n d i v i d u a l t e s t beams i n each s t r e s s l e v e l f o r each t e s t m a t e r i a l a r e shown i n F i g u r e s 33 - 41 . These i n d i v i d u a l p l o t s i l l u s t r a t e t he v a r i a b i l i t y i n c r e e p b e h a v i o u r w i t h i n each group w i t h the v a r i a b i l i t y i n i n i t i a l d e f l e c t i o n removed. The a v e r a g e f r a c t i o n a l creep f o r each t e s t group a t each s t r e s s l e v e l i s shown i n F i g u r e s 44 - 46 versus normal time and i n F i g u r e s 47 - 49 versus l o g time. The r e s u l t s a re presented i n a number of graphs f o r reasons of c l a r i t y s i n c e the 55 average v a l u e s f o r each t e s t group were c l o s e t o each other. The f i g u r e s show the same general t r e n d i n each s t r e s s l e v e l with the Parallam showing the lowest average f r a c t i o n a l creep and the 1650F D o u g l a s - f i r , the h i g h e s t . The f r a c t i o n a l creep r e s u l t s have a l s o been t a b u l a t e d i n T a bles 5A-5C. From these t a b l e s , a t the t e s t con-c l u s i o n (t=ll,210 h r ) , the average f r a c t i o n a l creep observed f o r each t e s t m a t e r i a l was as f o l l o w s : Average F r a c t i o n a l Creep S t r e s s L e v e l S t r e s s L e v e l S t r e s s L e v e l 1 2 3 1650F DF Mean 1.47 1.46 1.52 (%cv) (14.3) ( 8.0) (12.0) 2400F DF Mean 1.44 1.45 1.46 (%cv) ( 6.3) ( 7.2) ( 8.2) Parallam PSL Mean 1.40 1.42 1.43 (%cv) ( 7.1) ( 6.7) ( 7.0) The P a r a l l a m m a t e r i a l e x h i b i t e d l o w e r v a r i a b i l i t y i n f r a c t i o n a l creep compared t o the 1650F D o u g l a s - f i r group and s i m i l a r v a r i a b i l i t y to the 2400F D o u g l a s - f i r group. Again, the two 1650F D o u g l a s - f i r t e s t beams which exhibted high d e f l e c t i o n i n the d e f l e c t i o n v e r s u s time p l o t s a l s o e x h i b i t e d h i g h f r a c t i o n a l creep and i n c r e a s e d the c o e f f i c i e n t of v a r i a t i o n f o r the s t r e s s l e v e l 1 and 3 t e s t groups. 56 To observe the e f f e c t of s t r e s s l e v e l on the f r a c t i o n a l creep behaviour f o r the t h r e e t e s t m a t e r i a l s , the average f r a c t i o n a l creep r e s u l t s were r e - p l o t t e d i n F i g u r e s 58 - 60 w i t h a l l t h r e e s t r e s s l e v e l s on t h e same p l o t . I n s p e c t i o n of the p l o t s shows t h a t t h e r e appears to be l i t t l e i f any e f f e c t of s t r e s s l e v e l on the f r a c t i o n a l creep r e s u l t s f o r the P a r a l l a m and 2400F D o u g l a s - f i r t e s t groups. I t i s l e s s c l e a r w i t h the 1650F D o u g l a s - f i r group p a r t i c u l a r l y f o r the h i g h e s t s t r e s s l e v e l . To determine i f the e f f e c t of s t r e s s l e v e l on f r a c t i o n a l creep i s s i g n i f i c a n t a one-way a n a l y s i s of v a r i a n c e (ANOVA) s t a t i s t i c a l procedure (16) was performed on the t e s t data. T h i s procedure t e s t s the n u l l hypothesis (Ho) t h a t the f r a c t i o n a l creep means between the three s t r e s s l e v e l s are equal. The i n h e r e n t assumptions i n t h i s procedure of a p p r o ximately 'normal' d i s t r i b u t i o n s randomly sampled and w i t h s i m i l a r v a r i a n c e s are v a l i d f o r t h i s t e s t data. The r e s u l t s of t h i s a n a l y s i s f o r the 0.05 l e v e l of s i g n i f i c a n c e are summarized below at the average f r a c t i o n a l creep r e s u l t s a t the t e s t c o n c l u s i o n (t=ll,210 h r ) : A N O V A T e s t M a t e r i a l d. f . C a l c . F C r i t i c a l FQ.05 1650F D. f i r 93 0.87 3.11 2400F D. f i r 91 0.25 3.11 Parallam PSL 99 0.61 3.10 S i n c e none of the c a l c u l a t e d F v a l u e s a r e l a r g e r t h a n 57 the c r i t i c a l F v a l u e , we a c c e p t Ho and c o n c l u d e t h a t t h e r e i s no d i f f e r e n c e between t h e a v e r a g e f r a c t i o n a l c r e e p v a l u e s b e t w e e n s t r e s s l e v e l s f o r e a c h t e s t m a t e r i a l . S i m i l a r l y , an a n a l y s i s of v a r i a n c e s t a t i s t i c a l procedure can be performed on the f r a c t i o n a l creep data between t e s t m a t e r i a l s to determine i f there i s a d i f f e r e n c e i n performance. Since no s t a t i s t i c a l d i f f e r e n c e was found between s t r e s s l e v e l s f o r each of the t e s t m a t e r i a l s , the f r a c t i o n a l creep data f o r the three s t r e s s l e v e l s was combined and a one-way a n a l y s i s of v a r i a n c e performed on the t e s t data to t e s t the n u l l h y p o thesis t h a t the average f r a c t i o n a l creep performance between the three m a t e r i a l s i s equal. The r e s u l t s of the a n a l y s i s f o r the 0.05 l e v e l of s i g n i f i c a n c e are summarized below, a g a i n f o r the f r a c t i o n a l creep data a t the t e s t c o n c l u s i o n (t=ll,210 h r ) : F r a c t i o n a l Creep R e s u l t s T e s t M a t e r i a l n Mean %CV 1650F DF 94 1.48 11.9 2400F DF 92 1.45 7.2 Parallam PSL 100 1.42 7.0 C a l c . C r i t i c a l F F0.05 285 5.58 3.05 S i n c e the c a l c u l a t e d F i s g r e a t e r t h a n t h e c r i t i c a l F, we r e j e c t Ho and c o n c l u d e t h a t , a t l e a s t one of t h e 58 sample means i s d i f f e r e n t . To d e t e r m i n e w h i c h of t h e f r a c t i o n a l c r e e p means i s d i f f e r e n t , a Duncan's m u l t i p l e - r a n g e t e s t (16) was p e r f o r m e d . The r e s u l t s of the a n a l y s i s (see Appendix I ) show the mean f r a c t -i o n a l creep of the Parallam to be lower than t h a t of the 1650F D o u g l a s - f i r a t the 95% confidence l e v e l . No s t a -t i s t i c a l d i f f e r e n c e between the Parallam and 2400F D o u g l a s - f i r t e s t groups and between the 2400F and 1650F D o u g l a s - f i r groups was found a t the 95% confidence l e v e l . 5.2.3 D i s c u s s i o n The a n a l y s i s of the c r e e p r e s u l t s i n t h i s s t u d y was designed to determine i f the creep behaviour of Parallam PSL d i f f e r e d from t h a t of two c o m m e r c i a l l y a v a i l a b l e grades of MSR D o u g l a s - f i r lumber. The higher a l l o w a b l e bending s t r e s s f o r Pa r a l l a m w i t h the same MOE value as the 2400F D o u g l a s - f i r m a t e r i a l r e s u l t s i n h i g h e r i n i t i a l d e f l e c t i o n s when loaded t o i t s a l l o w a b l e bending s t r e s s . T h i s was c l e a r l y observed i n the creep d e f l e c t -i o n v e r s u s t i m e p l o t s . These p l o t s a l s o i n d i c a t e t h at the creep response f o r Pa r a l l a m i s s i m i l a r t o s o l i d sawn D o u g l a s - f i r . The higher a l l o w a b l e bending s t r e s s f o r Parallam i s of no advantage when used i n a d e f l e c t i o n - l i m i t e d a p p l i c a t i o n but the creep response would be expected to be no worse than MSR D o u g l a s - f i r m a t e r i a l . 59 The f r a c t i o n a l c r e e p b e h a v i o u r f o r P a r a l l a m i n t h i s study was shown t o be b e t t e r than the 1650F, 1.5E D o u g l a s - f i r c o n t r o l group. For a l l t e s t m a t e r i a l s a t the s t r e s s l e v e l s s t u d i e d , no s i g n i f i c a n t d i f f e r e n c e i n f r a c t i o n a l creep response w i t h s t r e s s l e v e l c o u l d be determined. The independence of f r a c t i o n a l creep w i t h a p p l i e d s t r e s s i s evidence of l i n e a r v i s c o e l a s t i c be-ha v i o u r . I d e n t i f i n g t h e range of s t r e s s e s f o r which these m a t e r i a l s e x h i b i t l i n e a r v i s c o e l a s t i c behaviour i s u s e f u l s i n c e w i t h i n t h i s r e g i o n , creep d e f l e c t i o n s can be c a l c u l a t e d f o r a r b i t a r y s t r e s s - h i s t o r i e s u s ing the s u p e r p o s i t i o n p r i n c i p l e . L i n e a r v i s c o e l a s t i c behaviour i s a l s o e v a l u a t e d by p l o t t i n g the creep compliance, J ( t ) a g a i n s t s t r e s s r a t i o and o b s e r v i n g l i n e a r behaviour (Dinwoodie (9)). Creep compliance can be expressed i n terms of f r a c t i o n a l creep t Cj and the i n i t i a l compliance, Jo, where J ( t ) = Jo (C f) (5.2) The i n i t i a l com p i i a n c e , J o , by d e f i n i t i o n i s t h e r e c i p r o c a l of t h e i n i t i a l modulus of e l a s t i c i t y , E o , which was independent of s t r e s s l e v e l . T h e r e f o r e , sinc e Jo and Cf were independent of a p p l i e d s t r e s s f o r a l l three t e s t m a t e r i a l s , we can c o n c l u d e t h a t t h e c r e e p compliance response i s a l s o independent of a p p l i e d s t r e s s and a l l t h r e e t e s t m a t e r i a l s i n t h i s study 60 e x h i b i t e d l i n e a r v i s c o e l a s t i c behaviour w i t h i n the range of a p p l i e d s t r e s s e s . 5.2.4 Summary A n a l y s i s of t h e c r e e p r e s u l t s of t h i s study f o r t h e t h r e e t e s t m a t e r i a l s 1650F,1.5E D o u g l a s - f i r , 2400F, 2.0E D o u g l a s - f i r and P a r a l l a m PSL a f t e r 15-1/2 months l o a d d u r a t i o n i n d i c a t e s t h a t : 1. t h e t i m e - d e p e n d e n t d e f o r m a t i o n b e h a v i o u r of P a r a l l a m PSL i s s i m i l a r t o s o l i d sawn machine s t r e s s r a t e d D o u g l a s - f i r lumber. 2. t h e f r a c t i o n a l c r e e p r e s p o n s e of the P a r a l l a m m a t e r i a l was f o u n d t o be l o w e r t h a n t h a t of the 1650F, 1.5E D o u g l a s - f i r m a t e r i a l . No s t a t i s t i c a l d i f f e r e n c e i n f r a c t i o n a l creep response was found between the P a r a l l a m and the 2400F, 2.0E Douglas-f i r m a t e r i a l or between the 2400F, 2.0E and 1650F, 1.5E D o u g l a s - f i r m a t e r i a l s f o r the s t r e s s l e v e l s s t u d i e d . 3. a l l three t e s t m a t e r i a l s e x h i b i t e d l i n e a r v i s c o e l a s t i c behaviour i n the range of s t r e s s l e v e l s studied. These s t r e s s l e v e l s exceed those g e n e r a l l y encountered i n s e r v i c e . CHAPTER SIX 61 MODELLING OF CREEP BEHAVIOUR Power Curve Model The c r e e p r e s u l t s were f i t t e d t o t h e power model i n t h e form of r e l a t i v e creep, C r, where C r = A t B . The r e s u l t s of the l i n e a r r e g r e s s i o n a n a l y s i s f o r the average r e l a t i v e creep f o r each t e s t m a t e r i a l a t each s t r e s s l e v e l are summarized below with t h e i r c o r r e l a t i o n c o e f f i c i e n t s : M a t e r i a l S t r e s s L e v e l Avg. R e l a t i v e C o r r e l a t i o n Type ( p s i ) Creep (C r) C o e f f . , r 0 3 57 1 1650F 2060 0.0193 t * 0.979 Douglas- 2325 0.0135 t 0 - 4 0 0 0.972 f i r 2575 0.0191 t°« 3 7 1 0 .977 2400F 3000 6.0244 t°« 3 3 S 0.977 Douglas- 3375 0.0230 t 0 ' 3 3 5 0 .975 f i r 3750 0.0249 t 0 ' 3 2 6 0 .977 Parallam 4000 0.0278 t 0 - 2 9 8 0 .989 PSL 4500 0.0323 t 0 - 2 8 6 0 .990 5000 0.0317 t°« 2 8 9 0 .991 1 time, t i n hours The r e s u l t s of the r e g r e s s i o n a n a l y s i s f o r the i n d i v i d u a l and average creep curves are summarized i n T a b les 7A-9c. The high c o r r e l a t i o n c o e f f i c i e n t observed i n d i c a t e t h a t the l i n e a r r e l a t i o n s h i p between the l o g a -rithm of r e l a t i v e creep and l o g a r i t h m of time i s a reasonable one f o r t h i s data. Comparison of the observed average d e f l e c t i o n and average r e l a t i v e creep with those p r e d i c t e d by these equations i s shown i n F i g u r e s 61-72. 62 The B parameter v a l u e s found f o r the average r e l a t i v e creep r e s u l t s ranged from 0.286 to 0.400 and are c o n s i s t e n t w i t h those r e p o r t e d by Hoyle (17) f o r nominal 4"x4" D o u g l a s - f i r beams i n bending who found v a l u e s which ranged from 0.287 to 0.366. L i t t l e f o r d (18) found v a l u e s ranging from 0.28 to 0.33 f o r glulam beams and Dinwoodie (9) r e p o r t s a value of 0.33 f o r timber i n g e n e r a l . The A parameter i s a measure of the r e l a t i v e creep a t t = l hour. The observed A v a l u e s ranged from 0.0135 to 0.0323 and are a l s o c o n s i s t e n t with those r e p o r t e d by Hoyle(17) and L i t t l e f o r d ( 1 8 ) . To observe how the power curve parameters A and B are i n f l u e n c e d by the beam modulus of e l a s t i c i t y (MOEt) a l i n e a r r e g r e s s i o n a n a l y s i s was done. The r e s u l t s of the a n a l y s i s , summarized i n F i g u r e s 73-74, do not show a s t r o n g c o r r e l a t i o n between the power curve parameters and MOEt. The B parameter shows a n e g a t i v e c o r r e l a t i o n with MOEt i n d i c a t i n g a tendency towards lower creep w i t h i n c r e a s i n g MOE, however, t h i s i s p a r t i a l l y negated by the A parameter which shows a s l i g h t p o s i t i v e c o r r e l a t i o n with MOEt and t h e r e f o r e a tendency towards higher creep with i n c r e a s i n g beam s t i f f n e s s . These r e s u l t s are c o n s i s t e n t with those r e p o r t e d by Hoyle et a l (17) f o r nominal 4"x4" Douglas-f i r beams i n bending where he found a negative c o r r e l a t i o n between r e l a t i v e creep and the wood e l a s t i c modulus. 63 6.2 L i n e a r V i s c o e l a s t i c Model The average r e l a t i v e creep equations as determined from the 4 parameter v i s c o e l a s t i c model are summarized below f o r each t e s t m a t e r i a l and s t r e s s l e v e l : M a t e r i a l S t r e s s L e v e l R e l a t i v e Creep 1 Type ( p s i ) < cr) 1650F 2060 0 .282 (1--exp(-.00250t) ) + .0000170t Douglas 2325 0 .278 (1--exp(-.00244t] ) + .0000157t - f i r 2575 0 .310 (1--exp(-.00236t) ) + .0000185t 2400F 3000 0 .269 (1--exp(-.00275t) ) + ,0000143t Douglas 3375 0 .273 (1--exp(-.00283t) ) + .0000144t - f i r 3750 0 .271 (1--exp(-.00284t; ) + .0000157t Parallam 4000 .0 .227 (1 -exp(-.00277t] ) + .0000135t PSL 4500 0 .237 (1 -exp(-.00284t; ) + ,0000137t 5000 0 .238 (1 -exp(-.00268t; ) + .0000146t 1 t i m e f t i n hours The parameters b j to b 4 f o r the i n d i v i d u a l and average d e f l e c t i o n curves f o r each m a t e r i a l type a t each s t r e s s l e v e l are summarized i n T a b l e s 7A-9C. From these parameters, b 5 and bg were c a l c u l a t e d u sing equations (2.11) and (2.12). Comparison of the observed average d e f l e c t i o n and average r e l a t i v e creep w i t h those p r e d i c t e d by these equations are shown i n F i g u r e s 61-72. To observe how the parameters b^, b5 and bg of the l i n e a r v i s c o e l a s t i c model f o r r e l a t i v e creep are i n f l u e n c e d by the beam modulus of e l a s t i c i t y (MOEt), a l i n e a r r e g r e s s i o n a n a l y s i s was done. The r e s u l t s 64 of the a n a l y s i s , summarized i n F i g u r e s 75-77 do not show strong c o r r e l a t i o n with any of the parameters as measured by the c o r r e l a t i o n c o e f f i c i e n t . The b s and bg parameters show a general negative c o r r e l a t i o n w i t h MOEt i n d i c a t i n g a tendency toward lower r e l a t i v e c r eep v a l u e s with i n c r e a s i n g beam s t i f f n e s s . I n s p e c t i o n of the parameters f o r the t e s t beams which f a i l e d during the study show t h a t t h e i r v a l u e s depend on the time under l o a d . T h i s was most e v i d e n t f o r the v i s c o u s flow parameter, b 4 , whose value tended to be much l a r g e r f o r the shorter p e r i o d s of time under l o a d . T h i s o b s e r v a t i o n i s i n agreement w i t h P i e r c e and Dinwoodie (9) who found f o r chipboard t h a t the estimate of b 4 f a l l s slowly as the l e n g t h of time the specimen i s under l o a d i s extended. They have f u r t h e r found t h a t an improved f i t to t h e i r creep data can be ob t a i n e d by modifying the 4-element v i s c o e l a s t i c model such t h a t the v i s c o u s flow term, b4t i s non-l i n e a r w i t h respect t o time. The m o d i f i e d 4-element model took the form : 6(t) = b± + b 2 ( l - e x p ( - b 3 t ) ) + b 4 t b 5 , 0 < b 5 < 1 (6.1) In t h i s model, the v i s c o u s flow component has a g r a d u a l l y reducing flow rate rather than a constant flow r a t e as i n the 4-parameter model. The r e s u l t s of t h i s study a l s o show evidence of a n o n - l i n e a r b 4 t term. T h i s can be observed i n Fi g u r e s 61-63 where the 65 observed d e f l e c t i o n s show a t r e n d towards an asymptotic va l u e w h i l e the p r e d i c t e d curve continues t o i n c r e a s e l i n e a r l y w i t h time. Though the 4-parameter model f i t t e d the experimental data w e l l f o r the time p e r i o d s t u d i e d , use of the model to p r e d i c t f u t u r e d e f l e c t i o n s must be used w i t h c o n s i d e r a b l e judgement. 6.3 D i s c u s s i o n and Summary I n s p e c t i o n of the d e f l e c t i o n curves p r e d i c t e d by the models i n F i g u r e s 61-63 shows the 4-parameter l i n e a r v i s c o e l a s t i c model to best f i t the observed d e f l e c t i o n s r e g a r d l e s s of t e s t m a t e r i a l type or a p p l i e d s t r e s s l e v e l . The power curve model d i d not f i t the data as w e l l d e s p i t e the high c o r r e l a t i o n c o e f f i c i e n t s o b t a i n e d from the l i n e a r r e g r e s s i o n a n a l y s i s . T h i s i s not a s u r p r i s i n g r e s u l t s i n c e f i t t i n g a model using 4 parameters i s expected to g i v e b e t t e r agreement than one using 2 parameters. I n s p e c t i o n of the r e l a t i v e creep curves p r e d i c t e d by the models i n F i g u r e s 64-72 shows the l i n e a r v i s c o e l a s t i c model to best f i t the observed r e l a t i v e creep r e s u l t s f o r the D o u g l a s - f i r m a t e r i a l , however, the f i t i s not as good as t h a t found f o r the d e f l e c t i o n r e s u l t s . The poorer f i t r e s u l t s from the procedure used to determine the parameters b$ and bg. These parameters were c a l c u l a t e d from the parameters determined from f i t t i n g the 66 4-parameter v i s c o e l a s t i c model to the d e f l e c t i o n data ( i . e . , b 5 = b 2 / b 1 and b 6 = b ^ b j j . If the estimate of the i n i t i a l d e f l e c t i o n , b j ^ from the curve f i t t i n g procedure d i f f e r e d from the a c t u a l observed i n i t i a l d e f l e c t i o n , <$o , then a systematic e r r o r was i n t r o d u c e d when bg a n c ; bg were c a l c u l a t e d . I t i s b e l i e v e d t h a t b e t t e r agreement would be obtained i f the r e l a t i v e c r eep data was f i t d i r e c t l y to the l i n e a r v i s c o e l a s t i c model C r = b 5 ( i - e x p ( - b 3 t ) ) + b 6 t ( 6 > 2 ) but t h i s was not proven i n t h i s study. The power curve model f i t the Parallam average r e l a t i v e c r eep r e s u l t s b e t t e r than the D o u g l a s - f i r m a t e r i a l s but o v e r e s t i m a t e d the creep a t the l a r g e r time i n t e r v a l s . The poorer f i t of v i s c o e l a s t i c model t o the r e l a t i v e creep r e s u l t s compared t o the d e f l e c t i o n r e s u l t s was f o r the same reason d i s c u s s e d f o r the D o u g l a s - f i r . In summary, based on the creep r e s u l t s of the study and the curve f i t t i n g procedure used, the a n a l y s i s i n d i c a t e s t h a t : 1. The 4-parameter v i s c o e l a s t i c model gave the best f i t data the creep data f o r the time p e r i o d s t u d i e d . There i s some i n d i c a t i o n t h a t a l i n e a r b 4 t term o v e r s i m p l i f i e s the v i s c o u s creep component. The parameters determined from the models a r e c o n s i s t e n t with those r e p o r t e d i n the l i t e r a t u r e . The v i s c o e l a s t i c model parameters developed p r o v i d e a b a s i s f o r e s t i m a t i n g the creep behaviour of lumber and Parallam under i n - s e r v i c e c o n d i t i o n s . 68 CHAPTER SEVEN CONCLUSIONS The r e s u l t s of t h i s study a p p l y t o t h e t i m e p e r i o d and s t r e s s l e v e l s i n v e s t i g a t e d and the temperature and r e l a t i v e humidity c o n d i t i o n s of an u n c o n t r o l l e d i n -t e r i o r environment. The a n a l y s i s l e a d s t o the f o l l o w i n g c o n c l u s i o n s : 1) No q u a n t i t a t i v e statement r e g a r d i n g the com-p a r a t i v e d u r a t i o n of l o a d performance of the Parallam PSL and HSR D o u g l a s - f i r m a t e r i a l can be made due to an i n s u f f i c i e n t number of r e p l i c a t i o n s a t the s t r e s s l e v e l s s t u d i e d . However the l i m i t e d t i m e - t o - f a i l u r e r e s u l t s suggests t h a t c u r r e n t d u r a t i o n of l o a d a d j u s t -ment f a c t o r s can be a p p l i e d to develop working s t r e s s e s f o r Parallam. 2) The time-dependent deformation (creep) beha-v i o u r of Parallam PSL was e q u i v a l e n t to 2400F, 2.0E D o u g l a s - f i r lumber and b e t t e r than 1650F, 1.5E D o u g l a s - f i r lumber. 3) A l l three m a t e r i a l s e x h i b i t e d l i n e a r v i s c o -e l a s t i c behaviour at the s t r e s s l e v e l s a p p l i e d . The 4-parameter v i s c o e l a s t i c model d e s c r i b e d the observed creep behaviour b e t t e r than the 69 power curve model. The r e s u l t s o b t a i n e d were c o n s i s t e n t with those r e p o r t e d i n the l i t e r a t u r e f o r wood and wood composites. 4) The model parameters presented p r o v i d e a b a s i s f o r e s t i m a t i n g the mean creep behaviour and v a r i b i l i t y i n creep response f o r dimension lumber and Parallam under i n - s e r v i c e l o a d c o n d i t i o n s f o r d r y - s e r v i c e environments. 70 BIBLIOGRAPHY (1) Hoyle f R.J., "Wood Technology i n the Design of Str u c t u r e s " , 4th e d i t i o n (1978). (2) Wood, L.W., " R e l a t i o n of Str e n g t h of Wood to Du r a t i o n of Load", F o r e s t Products L a b o r a t o r y , Report No. R-1916, Madison, Wisconsin (1951). (3) Madsen, B. and B a r r e t t , J.D., "Time-Strength R e l a t i o n s h i p f o r Lumber", S t r u c t u r a l Research S e r i e s , Report No. 13, Dept. of C i v i l E n g i n e e r i n g , U.B.C, Vancouver, B.C. (1976) . (4) F o s h i , R.O. and B a r r e t t , J.D. "Load D u r a t i o n and Bending S t r e n g t h : Hemlock Lumber", Jo u r n a l of S t r u c t u r a l D i v i s i o n of ASCE, (1980). (5) Bodig, J . and Jayne, B., "Mechanics of Wood and Wood Composites", Van Nostrand R e i n h o l d Company, N.Y. (1982). (6) N i e l s e n A., "Rheology of B u i l d i n g M a t e r i a l s " , N a t i o n a l Swedish C o u n c i l f o r B u i l d i n g Research, Stockholm, Sweden, Document D6 (1972) . (7) G r e s s e l , P. "A Proposal f o r C o n s i s t e n t Experimen-t a l P r i n c i p l e s f o r Conducting and E v a l u a t i n g Creep Tests (Vorschlag e i n h e i t l i c h e r Prufgrundsatze zur Durchfuhrung und Bewertung von Kriechversuchen), Holz a l s Roh-und Werkstoff, Volume 44, 1986, pg 133-138. (8) P i e r c e , CB., Dinwoodie J . M., "Creep i n Chipboard", Part I - J . M a t e r i a l s S c i . 12:1955-1960 (1977) , Parts II-V-Wood S c i . Technology (part 11-13:265-282(1979), Part 111-15:125-144 (1981), Part IV-18:205-224(1984), P a r t V-19:83-91(1985) (9) Dinwoodie, J.M., "Timber, i t s Nature and Behaviour", Van Nostrand R i e c h o l d Company, N.Y. (1981). (10) American S o c i e t y f o r T e s t i n g and M a t e r i a l s (ASTM), D198-76, "Standard Methods of S t a t i c T e s t s of Timbers i n S t r u c t u r a l S i z e s " (1979). (11) American S o c i e t y f o r T e s t i n g and M a t e r i a l s (ASTM), D2915-84", E v a l u a t i n g A l l o w a b l e P r o p e r t i e s f o r Grades of S t r u c t u r a l Lumber" (1979). (12) G a l l i g a n , W.L., "A Status Report - Nondestructive T e s t i n g of Wood", Fores t Products J o u r n a l , 14(5): 221-227 (1964). 71 (13) Wood Handbook, r e v i s e d e d i t i o n , Handbook No. 72 US Department of A g r i c u l t u r e , 1974. (14) Armstrong, L.D. and C h r i s t e n s e n , G.N., "Influence of Moisture Changes on Deformation of Wood Under S t r e s s " , Nature 191, Pg. 869-870 (1961). (15) Hoyle, R.J. et a l , "Creep of Douglas F i r Beams Due to C y c l i c Humidity C o n d i t i o n s " , Wood F i b e r Science 18(3) (1986). (16) Walpole, R., " I n t r o d u c t i o n t o S t a t i s t i c s " , MacMillan P u b l i s h i n g Company, Inc., Chapter II (1974). (17) Hoyle, R.J. et a l , "Primary Creep i n Douglas F i r Beams of Commercial S i z e and Q u a l i t y " , Wood F i b e r Science 17(3) (1985). (18) L i t t l e f o r d , T . W . : "Performance of Glued-Laminated Beams Under Prolonged Loading", F o r e s t Products Laboratory Information Report VP-X-15(1966). 73 International Conference of Building Officials EVALUATION REPORT Report No. 4217 November, 1984 Filing Category: DESIGN—Wood PARALLAM™ PARALLEL STRAND LUMBER (PSL) MACMILLAN BLOEDEL LIMITED PARALLAM DIVISION 1272 DERWENT WAY ANNACIS ISLAND, B.C., CANADA V3M SRI I. Subject: Parallam'" Parallel Strand Lumber (PSL). II. Description: General: Parallam is manufactured by laminating Douglas fir strands with an exterior-type adhesive (phenol-formaldehyde). Strands are coated with adhesive, oriented to the length of the member, fed into a press in the desired lay-up pattern and then compressed under heat and pressure. Quality control testing and inspections are provided by the Amer-ican Plywood Association. Design and Allowable Stresses: Design provisions for solid-sawn lum-ber in Chapter 25 of the code are applicable to Parallam unless otherwise noted in this report. Allowable unit stresses for dry conditions of use are noted in Table No. I. Lateral nail resistance and nail withdrawal values are as provided in the code for Douglas fir sawn lumber. Nails installed perpendicular to the wide face of strands may be installed in accordance with the code. Nails installed parallel to the wide face of strands must be spaced a minimum of 3 inches on center for 8d nails and 4 inches for lOd nails. See Figure No. 1 for details on strand orientation. Bolt design values are as provided in the code for Douglas fir. Specific approval is required for other than nailed and bolted connections noted herein. The fire-resistance of Parallam may be considered equivalent to similar sizes of solid-sawn lumber where Type IV heavy timber con-struction is required. Identification: Parallam is identified with a label, stamp or stamps noting the name and plant number of the manufacturer, the ICBO evaluation report number and the quality control agency, American Plywood Associa-tion (AA-502). III. Evidence Submitted: Mechanical properties test data, fastener test data, long-term load test data and fire test data, along with a quality control manual. Findings IV. Findings: That Parallam™ Parallel Strand Lumber (PSL) is an alternate construction material to that specified in the 1982 Uniform Building Code, subject to the following conditions: 1. Fabrication and quality control are in accordance with this report. 2. The design stresses do not exceed those set forth in Table No. I. 3. The material is not used where a moisture content exceeding 19 percent can result. This report is subject to re-examination in one year. TABLE NO. I—ALLOWABLE DESIGN STRESSES FOR PARALLAM'" PARALLEL STRAND LUMBER (Pounds per Square Inch) FLEXURAL STRESS* TENSION PARALLEL TO GRAIN COMPRESSION PARALLEL TO GRAIN Fc COMPRESSION PERPENDICULAR TO GRAIN HORIZONTAL SHEAR r, MODULAS of ELASTICITY (MOE) Load Direction Load Direction Parallel to wide face of etrand Perpendicular to wide face of strand Parallel to wide face of strand Perendlcular to wide face of strand 2800 2200 2800 600 400 250 165 2,000,000 'For 12-inch depth; for other depths, muliply by (12/d)1™, as shown below. For depths less than 3.S inches and for flat bending, use the factor for 3.5-inch depth. Depth Onches) 3.5 5.5 7.25 9.25 11.25 13.25 Multiplier 1.15 1.09 1.06 1.03 1.01 0.989 PERPENDICULAR TO WIDE PACE OF STRAND FIGURE NO. 1 ICBO evaluation reports are issued solely to provide information to Class A members of the organization utilizing the code upon which the report is based. Evaluation reports are not to be construed as representing aesthetics or any other attributes not specifically addressed nor as an endorsement or recommendation for use of the subject report. This report is based upon independent tests or other technical data submitted by the applicant. The ICBO technical staff has reviewed the test results and!or other data, but does not possess test facilities to make an independent verification. There is no warranty by ICBO, expressed or implied, as to any "Finding" or other matter in the report or as to any product covered by the report. This disclaimer includes, but is not limited to, merchantability. Figure 2: Parallam PSL code report Page 1 of 1 o o 2. o 2 £ 2 3 g m a- H * > P o § I 5T co f--I ft cn / SE.C0HO IMinure I HOUR I DAY I MOUTH I YEAR 10 YEARS SO /OO Duration of Maximum Load STRESS RATIO VS. LOG CD MEDIAN TIMES S MADISON 1HYPERBOLIC' CURVE . 1 minute HEMLOCK LUMBER CURVE MADISON LINEAR TREND LINE 2 months ,10 years -3.08 -2.03 -1.00 0.00 1.00 —I 2.00 LOG T 3.00 4.03 5.00 6.02 Figure 4 : Comparison of duration of load results of 2x6 Hemlock lumber (No. 2 & better) to the Madison Curve (from Foschi & Barrett , 1980) 7.00 76 JJ TJ Time a) Figure 5. : Creep behaviour: a) selected load levels b) corresponding deflections and stages of creep c) creep rate 77 Creep Creep A Time Stress Temperature Creep Rei.. Hurnidity Varying Temperature or Relative Humidity (constarj stress) Constant Climate (constant! stress) Time fit t r e s s Creep Strain I n i t i a l creep Time -_RecoveryJxaxrve Reloading curve Figure 6 : Factors affecting creep (from Nielsen,1972) Douglas-Fir Population Div i s ion by Modulus of E l a s t i c i t y Increasing MOE ^ Block 1 Block 2 Block 3 Block 34 Short Term Flexure Stress Level 1 Stress Level 2 Stress Level 3 I Creep/Rupture Study 1 Fig 7 : Schematic Diagram of Douglas-fir Population Div i s ion Procedure. Increasing MOE ^ Block 1 Block 2 Block 3 Block 4 Block 60 : ' Stress Level 1 Stress Level 2 Stress Level 3 Working groups not part of study I — » ' Creep/Rupture Study VO Fig 8 : Schematic Diagram of Parallam PSL Population Division Procedure. 80 Machine Cross Head Load Evener—-|» Load Bearing Block Load Bearing Roller ocker Type eaction Reaction Bearing Plate 24.5 in Test Beam Machine Base 24.5 i n I Bea Der: Rollers Reaction 1 24.5 i n 73.5 i n Fig 9 : Schematic Diagram of Flexure Test Setup. Carbon S t e e l 0.4 in. 4.8 in. 5.6 in. SIDE VIEW Figure 10 : Schematic Diagram of a Moment Arm Load Test J i g t 82 LEGEND: J i g Number 1 to 306 M a t e r i a l S t r e s s Type L e v e l P S L - P a r a l l a m t m 1 2.0E-D.F. 2400F 2 1.5E-D.F. 1650F 3 180' Lever Arm Wt. A - 22.0 l b B - 23.7 l b C - 27.0 l b Figure 11 : Warehouse test arrangement 1650F.1.5E DflR - M.O.R SHORT TERM STRENGTH RESULTS (M.C.=12X) 2.0 4.0 6.0 8.0 10.0 12.0 14.0 (Thousands) M.O.R. (psi) Figure12 1650F.15E D.FIR - M.O.E SHORT TERM STRENGTH RESULTS (M.C.-12X) 1.1 1.3 1.5 1.7 1.9 2.1 2.3 2.5 MO.E. (million pat) Figure 13 2400F.2.0E D. FIR - M.OJ*. SHORT TERM STRENGTH RESULTS (M.C.=12X) 5.(300 5.000 7.000 9.000 11.000 13.000 15.000 (Thousands) M.O.R. (pst) Figure 14 2400FZ0E D. FIR - M.O.E SHORT TERM STRENGTH RESULTS (M.C.=12X) 1.400 1.600 1.800 2.000 2.200 2.400 2.600 2.800 M.O.E. (million psi) Figure 1 5 PARALLAM PSL-M.OJL SHORT TERM STRENGTH RESULTS (M.C.= 12X) 4.000 6.000 8.000 10.000 12.000 14.000 (Thousands) M.O.R. ( psi ) Figure 1 6 PARALLAM PSL - MXXE SHORT TERM STRENGTH RESULTS (M.C.=12%) 1.600 1.800 2.000 2.200 2.400 M.O.E. (million pst) Figure 1 7 — in °- c • in X 0 15.0 -14.0 -13.0 -12.0 -11.0 --i 10.0 9.0 8.0 -| 7.0 -6.0 • 5.0 - j 4.0 -] | i 3.0 1650F.1.5E DOUGLAS-FIR 2.0 MOR = -1836 + (5.198E-3)M0E r = .650 n = 66 + 1.00 1.20 1.40 1.60 1.80 2.00 2.20 2.40 2.60 2.80 3.00 M.O.E. (E6psi) 00 VO FigureT8 2400F.2.0E DOUGLAS-FIR MOR = -3507 + (5.880E-3)MOE r = .615 n = 69 + + + ~ i — r ~ i — r 1.00 1.20 1.4-0 1.60 1.80 2.00 2.20 M.O.E. (E6psi) Figure 19 2.40 2.60 2.80 3.00 91" ( s p u D s n o m ) ( i s d ) -yo'rN E Q U I L I B R I U M M O I S T U R E C O N T E N T ( * ) CO 4^  H-CO IT) D 3 N 00 :*> -I o CD I > c I o CD O ». c_ c 3 o I CD TJ 1^ b 00 b b o b o b b b b " A 33 m I o c: to m O CD 70 o LO —I TO m o o m 36 14.0 z u I--z o u LU QC D h-U) O 2 13.0 12.0 1 1.0 10.0 9.0 8.0 7.0 6.0 1 B-1 ' 1 ' 1 1 1 ' ! 1  09-Mar-84 17-Jun-84 25-Sep-84 03-Jan-85 1 3-Apr - 8 5 2 2 - J u l - 8 5 a 1650F.1.5E D.FIR + 2400F.2.0E D.FIR O PARALLAM P.S.L. CO Figure 22: Specimen moisture content changes in test warehouse 94 FIGURE 23 : PLOTS OF MOEt u s . MOEa FOR THE THREE TEST GROUPS z o t~ u u u. u Q 0. Ul U CC u 0.130 CREEP DEFLECTION DATA 1650F.1.5E DFIR - SL1 (2060psi),n=34 0.000 2000 4000 6000 8000 T I M E t-hfo u r s ) 10000 12000 in Figure 24 z o r-u LLI _ J Lu LU Q CL LU LU rr u CREEP DEFLECTION DATA 2400F.2.0E DFIR - SL1 (3000 PSI),n=34 2000 4000 6000 8000 T I M E ( h o u r s ) 1 0000 12000 Figure 2 5 z o (-o _l u. Ul Q Q. Ul Ul oa u 0.130 0.120 -0.110 -J 0.100 -0.090 0.080 0.070 0.060 0.050 0.040 0.030 0.020 -0.010 -0.000 2000 CREEP DEFLECTION DATA PARALLAM P.S.L - SL1 (4000psi),n = 34 -partial beam failure (no mojre d e f l e c t i o n s recorded) 4000 6000 8000 T I M E ( h o u r s ) 10000 12000 1X5 Figure 26 CREEP DEFLECTION DATA 1650F.1.5E DFIR - SL2(2325psi),n = 34 z o (-o LU _i b. u a a. Ld u on u 2000 4000 6000 8000 T I M E ( h o u r s ) 10000 12000 1£> CO , Figure 27 CREEP DEFLECTION DATA 2400F.2.0E DFIR - SL2(3375psi),n=34 z o h-o u _J ii. u • o. u u cc u 2000 4000 6000 8000 T I M E ( h o u r s ) Figure 28 10000 12000 vo vo 0.130 — 0.120 — 0.1 10 -0.100 -0.090 6 z 0.080 o / f-u 0.070 — u u —I u. LLI 0.060 — 1 Q 0. Ul 0.050 -U CC U 0.040 — 0.030 -0.020 — 0.010 0.000 CREEP DEFLECTION DATA PARALLAM P.S.L. - SL2 (4500psi) ,n=34 2000 4000 6000 8000 T I M E ( h o u r s ) Figure 29 10000 12000 H O o CREEP DEFLECTION DATA 1650F.1.5E DFIR - SL3(2575ps i ) , n =34 Figure 30 CREEP DEFLECTION DATA z o h-u u _j u. u Q CL. u LU cc o 2400F.2.0E DFIR - SL3(3750p Sf),n=34 2000 4000 6000 8000 10000 T I M E ( h o u r s ) F i g u r e 31 1 2000 H O £ z o (— o LU -I U. LU Q Q. LU LU a: u 2000 CREEP DEFLECTION DATA PARALLAM P.S.L. - SL3 (5000ps!) ,n=34 4000 6000 8000 T I M E ( h o u r s ) F i g u r e 3 2 10000 12000 o CO FRACTIONAL CREEP DATA 1650F.1.5E D.FIR - SL1 (2060psi),n=34 n hi u cc u < z o r-o < DC U. 2000 4000 6000 8000 T I M E ( h o u r s ) Figure 33 10000 1 2000 o FRACTIONAL CREEP DATA 2 4 0 0 F . 2 . 0 E D.FIR - SL1 ( 3 0 0 0 p s i ) , n = 3 4 Q_ Ul Ul Q: o _ i < z o I— u < ot: u. 2 0 0 0 4 0 0 0 6 0 0 0 8 0 0 0 T I M E ( h o u r s ) Figure 3 4 FRACTIONAL CREEP DATA 4 0 0 0 6 0 0 0 8 0 0 0 T J W E ( h o u r s ) Figure ,35 1 0 0 0 0 1 2 0 0 0 o cn FRACTIONAL CREEP DATA Figure. 3 6 FRACTIONAL CREEP DATA Figure 37 FRACTIONAL CREEP DATA T I M E ( h o u r s ) Figure 38' FRACTIONAL CREEP DATA Figure-39 FRACTIONAL C R E E P DATA 2400F.2.0E D.FIR - SL3 (3750psi),n~34 2.5 ^ ; ' , ; i , ; : i ; ; ; I ! I I 2.4 -I ! ! ! I ! i i I 0 2000 4000 6000 8000 10000 12000 T I M E ( h o u r s ) Figure 40 FRACTIONAL C R E E P DATA Figure 41 AVG. CREEP DEFL'N VS TIME LU Q a. LU LU DC U O > < • 1 650f DF1R 2000 4000 6000 8000 M E (hours) 4- 2400f DFIR 10000 12000 U l PARALLAM Figure 42 AVG. FRACTIONAL C R E E P vs TIME STRESS LEVEL ONE 2.00 - i 1 • 1 1 — 1.90 -1.80 -1.00 -IS 0.90 -f 1 : 1 1 1 ""I 0 2000 4000 6000 8000 10000 12000 TIME ( hours ) • 1650f DFIR(2060psi) + 2400f DFIR(3000psi) O PARALLAM (4000psi) Figure 44 AVG.FRACTIONAL CREEP vs TIME STRESS LEVEL TWO u Ld OC u < z o f~ o < > < o 2000 4000 6000 8000 10000 • 1650f DFIR(2325psi) TiME ( hours ) + 2400f DFiR(3375psi) PARALLAM (4500psi) 12000 Figure 4 5 AVG. FRACTIONAL C R E E P vs TIME STRESS LEVEL THREE a. u LU a: o _j < z o \-o < a: > < 1.00 -II 0 2 0 0 0 4 0 0 0 6 0 0 0 8 0 0 0 1 0 0 0 0 12000 • 1650f DFIR(2575ps i ) O TIME ( hou rs ) + 2 4 0 0 f DF IR(3750ps i ) PARALLAM ( 5 0 0 0 p s ; ) Figure 4 6 AVG.FRACTIONAL CREEP vs TIMEdog scale) STRESS LEVEL ONE 0-u Ul CC u < z o I-o < CC u. 6 > < 0.90 100 10000 • 1650f DFIR(2060psi) O TIME ( hours ) '+ 2400f DFIR(3000ps!) PARALLAM (4000psi) Figur e -47 AVG.FRACTIONAL CREEP vs TIMEdog scale) S T R E S S L E V E L T W O ui u tc o < o t— o < 01 Lu 6 > < 2.00 1.00 0.90 0.01 1 100 10000 • 1650f DFlR(2325psi) TIME ( hours ) + 2400f DFiR(3375psI) PARALLAM (4500psi) vp Figure 4 8 AVG.FRACTIONAL C R E E P vs TIMEdog scale) STRESS LEVEL THREE 0-UJ Ld OC U _1 < z o f— o < cc > < 0 .90 0.01 1 100 1 0 0 0 0 • 1650 f DFIR(2575ps i ) TIME ( hou rs ) + 2 4 0 0 f DFIR(3750ps I ) PARALLAM ( 5 0 0 0 p s i ) H to o Figure 49 % SURVIVAL VS TIME < > > 100.0 1650F.1.5E DOUGLAS FIR 90.0 H 80.0 70.0 60.0 H 50.0 100.0 10000.0 TIME (hours) • SL 1 (2060 psi) + SL 2 (2325 psi) O SL 3 (2575 psi) h-1 Figure 50 < > > ac 3 100.0 90.0 H 80.0 70.0 60.0 H 50.0 -f • SL 1 (3000 psi) % SURVIVAL VS TIME 2400F 2.0E DOUGLAS FIR 100.0 TIME (hours) + SL 2 (3375 psi) SL 3 (3750 psi) 10000.0 to Figure 51 % SURVIVAL VS TIME PARALLAM PSL 100.0 90.0 -80.0 -70.0 -60.0 -50.0 -| 1 1 1 1 r 1 0.0 1.0 100.0 10000.0 TIME: (hours) • SL 1 (4000 ps!) t SL 2 (4500 ps!) O SL 3 (5000 psi) Figure 52 CUMLATIVE PROBABILITY 2400F.2.0E D. FIR - M.O.R. FLEXURE RESULTS - SURVIVORS (M.C.=12X) 3.000 5.000 7.000 9.000 11.000 13.000 15.000 (Thousands) M.O.R. (psi) Figure 54 C U M U L A T I V E P R O B A B I L I T Y o o o o o O) o o o • o o o 03 o • o o o *1 ft as o . c M w p-09 # O o o o o o • o o o o o o •Eh. • I I I cn co co L-1 Ir1 tr1 OJ to I—1 Ul •£» rf^ o u i o o o o o o o TJ TJ TJ ca co cn H- H- H-to o o o 9ZT TIME (hours) Figure 5 6 : STRESS RATIOS USING CONTROLS TIME (hours) Figure 57 : STRESS RATIOS USING TEST DATA AVOFRACTIONAL CREEP vs STRESS LEVEL 1650F.1.5E DOUGLAS FIR 1.60 n 0 2000 4000 6000 8000 10000 12000 TIME ( hours ) • 2060 psi + 2325 psi O 2575 psi Figure 58 1.60 AVdFRACTIONAL CREEP vs STRESS LEVEL 2400F.2.0E DOUGLAS FIR 1.50 H 1.00 a 1 1 1 1 1 1 1 1 1 1 1 1 0 2000 4000 6000 8000 10000 12000 TIME ( hours ) • 3000 psi + 3375 psi O 4000 psi Figure 59 a. bi ui tic o J < z o u < oc Ik • > < 1.60 1.50 H 1.40 1.30 1.20 H 1.10 1.00 AVG.FRACT10NAL CREEP vs STRESS LEVEL PARALLAM PSL 2000 4000 6000 • 4000 ps! TIME ( hours ) + 4500 ps! i 1 r 8000 10000 O 5000 ps! 12000 H Figure 6 0 0.075 I650F. 15E DOUGLAS FIR AVG.CREEP DEFLN - OBSERVED VS PREDICTED 0.07 H Figure 61 2400F, 2.0E DOUGLAS FIR AVG.CREEP DEFLN - OBSERVED VS PREDICTED 0.08 - i 0.075 H TIME (hours) + SL1 (3000 psi) O SL2 (3375 psi) X SL3 (3750 psi) Figure 6 2 PARALLAM PSL + SLl (4000 p,|) TIME (hour.) X SL3(S000 p„ ) ° S L 2 ( « 0 0 P „ ) Co Figure 63 6 0 . 0 5 0 . 0 4 0 . 0 H X 3 0 . 0 2 0 . 0 1 0 . 0 . X - -// L i n e a r V i s c o e l a s t i c Model Power Curve Model C r = b 5 ( 1 - e x p [ - b 3 t ] ) + b 6 t B At 0 . 0 -%r 0 2 0 0 0 4 0 0 O " T 6 0 0 0 TIME (hours ) X e x p e r i m e n t a l do to T S 0 0 0 . _ 7 r 0 0 O 0 1 2 0 0 0 Figure 64 1650F, L5E DOUGLAS FIR - SL2 AVG. REL. CREEP - OBSERVED VS PREDICTED 60.0 50.0 40.0 X 50.0 / " X 20.0 1/ 10.0 -L i n e a r V i s c o e l a s t i c Model C r = fc>5(1-exp[-b3't ]) + b g t B Power Curve Model C = At r 0.0 -% 1 1 O 2000 1 r —i r-6000 40 CO 8C»00 1 0000 12000 TIME (hours) X experimental data Figure 65 60.0 1650R15E DOUGLAS FIR - SL3 AVG. REL. CREEP - OBSERVED VS PREDICTED 50.0 -3_ 40.0 -X 0-U l LLI CC o > UJ a: 30.0 20.0 10.0 L i n e a r V i s c o e l a s t i c Model C r = b 5 ( i - e x . p [ - b 3 t ] ) + b g t : B — — — Power Curve Model C = At r 0.0 —I 2000 0 4000 6000 1 1 1 8000 10000 12000 TIME (hours) experimental data Figure 66. K Co 2400F, 2.0E DOUGLAS FIR - SLl A V G . R E L . C R E E P - O B S E R V E D V S PREDICTED 6 0 . 0 ft. UJ Ul rX O UJ > < _ l Ul a: 5 0 . 0 40.0 X 30.0 20.0 L i n e a r V i s c o e l a s t i c Model C r = h> 5(1-exp[-k> 3t ] ) + b g t B 10.0 — — Power Curve Model C = At r 0 ?000 4000 1 6000 8000 10000 12000 TIME (hours) X experimental data CO' Fiqure 6 7 2400F, 2.0E DOUGLAS R R - SL2 AVG. REL. CREEP - OBSERVED. VS PREDICTED so.o 1. ft. ixi UJ ftC O UJ > < IxJ ft: 50.0 40.0 50.0 10.0 0.0 X L i n e a r V i s c o e l a s t i c Model C = b c (1 -exp[ - b 0 1 ] ) + b,-t r b 3 6 B — •——* Power Curve Model C = At r 0 "1 1— 2000 4000 6000 8000 1 1 0000 12000 TIME (hours) X experimental data LO 60.0 2400F, 2.0E DOUGLAS FIR - SL3 AVG. REL. CREEP - OBSERVED VS PREDICTED 50.0 O 40.0 X X"" 0. UJ UJ cc o Ul > Ul CC 30.0 20.0 10.0 -I L i n e a r V i s c o e l a s t i c Model C r = b g ( 1 - e x p [ - b 3 t ] ) + b g t B Power Curve Model C = At r o.o .-j|e o 2000 4000 6000 8000 I 10000 1 2000 X TIME (hours) experimental data i H ! ' ' 0 Figure 69: 60.0 PARALLAM PSL - SLl AVG. REL. CREEP - OBSERVED VS PREDICTED 50.0 o 0. IfJ IrJ o ifj > UJ 40.0 30.0 20.0 10.0 X L i n e a r V i s c o e l a s t i c Model C r = b 5 ( 1 - e x p t - b 3 t ] ) + . b g t B — i — —- Power Curve Model C = At r 0.0 -5£- 1—-8000 0 2000 r 4000 I 6000 TIME (hours) experimental data 0000 12000 Figure 70 PARALLAM PSL - SL2 AVG. REL. CREEP - OBSERVED VS PREDICTED 60.0 - i 50.0 -8 ft. IfJ IfJ ec o > i— Ul AC X 40.0 30.0 20.0 10.0 L i n e a r V i s c o e l a s t i c Model C r = b g d - e x p [ - b 3 t ] ) + b g t B — Power Curve Model C = At r 0 . 0 -%r o T 2 0 0 0 4O0O 6 0 0 0 TIME (hours) e x p e r t m e n t a I d a t a 8 0 0 0 1 0 0 0 0 1 2 0 0 0 Figure 71 PARALLAM PSL - SL3 AVG. REL. CREEP - OBSERVED VS PREDICTED 60.0 -i 50.0 H O 2000 4000 6000 8000 10000 12000 TIME (hours) X experimental data Figure 7 2 12.00 11.00 10.00 9.00 8.00 7.00 6.00 5.00 4.00 3.00 2.00 1.00 0.00 COEFFICIENT A vs MOEt (ALL DATA) V A = 0.239 + 1.122(MOEt) r = 0.214 -H-'X^x^>X x x $ XOXXOX x x . 6 ^ 0 x T 1.40 T 1.00 1650F DFIR 1.80 2.20 MOEt (E6 ps!) 2400F DFIR 2.60 X PARALLAM PSL 3.00 Figure 7 3 0.55 EXPONENT B vs MOEt (ALL DATA) 0.50 H 0.45 ~i 0.40 0.35 H 0.30 H 0.25 H 0.20 H + V ++ + + + +-b. + * 7 + + + + ° x • ++ + x o +<*>o+ A , o + ++ ++ + + +o K/° ~ o *& x #o X + + o O o d ^ oX * x o o x x o o o 0.15 H B= 0.542 - 0.097 (MOEt). r = -0.431 0.10 1.00 1650F DFIR 1.40 1.80 2.20 2.60 3.00 MOEt (E6 pst) O 2400F DFIR X PARALLAM PSL Figure 7 4 10.00 b3 parameter vs MOEt (ALL DATA) 9.00 -8.00 -7.00 -6.00 -5.00 -4.00 -3.00 -2.00 -1.00 -0.00 b3 = 1.780 + 0.486(MOEt) r = 0.159 + +4- + + + O  X * X + x x o Q oo T — i — i — i — i — h — i — i — i — i — i — i — i — i — i — i — i — i — i — I 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 1 1650F DFIR MOEt (E6 psi) O 2400F DFIR X PARALLAM PSL Figure 75 0.60 b5 parameter vs MOEt e •4-e E o i. o a m A 0.50 0.40 H 0.30 H 0.20 H 0.10 0.00 O <0 b = 0.429 -t = -0.347 0.080(MOEt) • o o ° + , o + + I 1 1 1 1 1 1 r— 1 1.2 1.4 1.6 1.8 "I 1 1 1 1 1 1 1 1 1— 2 2.2 2.4 2.6 2.8 3 + 1650F DFIR MOEt (E6 pst) O 2400F DFIR X PARALLAM PSL Figure 76 7.00 b6 parameter vs MOEt 6.00 H 5.00 H 4.00 H 3.00 H 2.00 -4 1.00 H 0.00 b g = 2.475 - 0.497(MOEt) r = -0.274 + 4- ° * O " 1 — I — I — I — I — I — I — I — I — I — I — I — I — I — I — I — I — I — I — 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 1650F DFIR MOEt (E6 psi) O 2400F DFIR X PARALLAM PSL Figure 77 149 TABLE 1 POPULATION DIVISION - SUMMARY DOUGLAS-FIR MOE VALUES 1650 F f 1.5 E D o u g l a s - F i r Short Term F l e x u r e Long Term Creep/Rupture 2060 p s i 2325 p s i 2575 p s i Average MOEa % cv (106 p s i ) max. min. n 1.58 13.9 2.20 1.18 66 1.60 14.9 2.27 1.20 34 1.59 13.8 2.08 1.21 34 1.59 14.0 2.12 1.22 34 2400F, 2.0E D o u g l a s - F i r Short term F l e x u r e Long Term Creep/Rupture 3000 p s i 3375 p s i 3750 p s i Average 2.00 2.06 2.06 2.07 MOEa % cv 9.6 12.6 11.7 12.2 (106 p s i ) max. 2.63 2.77 2.61 2.70 min. 1.66 1.55 1.61 1.68 n 69 34 34 34 150 TABLE 2 POPULATION DIVISION - SUMMARY PARALLAM™ PSL MOE VALUES P a r a l l a m t m P a r a l l e l Strand Lumber Short Term Fl e x u r e Creep/Rupture Average MOEd % CV (10^ Maximum p s i ) Minimum n 2. 30 7.7 2.66 1 .90 60 2.28 6.8 2.68 2.01 1 02 \ Parallam P a r a l l e l Strand Lumber Long Term Creep/Rupture Study 4000 p s i 4500 p s i 5000 p s i Average 2.03 2.03 2.03 % CV 6.6 6.4 6.4 MOEa Maximum 2.28 2.29 2.29 (1 0 6 Minimum 1 .76 1 .79 1 .80 p s i ) n 34 34 34 151 TABLE 3 A SHORT TERM STRENGTH FLEXURE RESULTS Moisture Content at Test Y\ n Moisture Content (%) Specific Gravity Propor'nl Limit Stress (psi ) Modulus of Rupture (psi) Modulus of elasticity (10 6psi) 1650F, 1.5E Douglas-Fir Avg (%cv) 66 12.7 (10.6) 0.445 ( 8.7) 4275 (21 .1 ) 6800 (30.1 ) 1 .66 (15.6) 2400F, 2.0E Douglas-Fir Avg (%cv) 69 13.1 ( 5.9) 0.481 ( 7.7) 5496 (22.5) 8907 (25.4) 2.12 (11.2) Parallam PSL Avg (%cv) 60 12.7 (12.6) 0.556 ( 3.9) 5778 (11.2) 9845 (13.3) 2.03 ( 8.6) TABLE 3B Moisture Content Adjusted to 12%* TEST GROUP X n Moisture Content (%) Specific Gravity Propor'nl Limit Stress (psi ) Modulus of Rupture (psi) Modulus of elasticity (106 p si) 1650 F, 1.5E Douglas-Fir Avg (%cv) 66 12.0 0.446 ( 8.7) 4353 (20.6) 6923 (29.6) 1 .68 (15.6) 2400F, 2.0E Douglas-Fir Avg (%cv) 69 12.0 0.484 ( 7.9) 5651 (23.7) 9146 (25.7) 2.15 (11.5) Parallam PSL Avg (%cv) 60 12.0 0.558 ( 4.0) 5882 (10.4) 1 0037 (14.0) 2.05 ( 7.9) (*) as per ASTM D2519 test methods 152 TABLE 4 A FLEXURE TEST RESULTS FOR DURATION OF LOAD SURVIVORS Moisture Content at Test K n Moisture Content (%) Specific Gravity Propor'nl Limit Stress (psi ) Modulus of Rupture (psi ) Modulus of El a s t i c i t y (10 6psi) 1650F, 1.5E Douglas-fir Avg (%cv) 97 11.5 ( 3.2) .456 (8.5) 3805 (16.8) 7112 (31.3) 1 .75 (16.1 ) 2400F, 2.0E Douglas-fir Avg (%cv) 92 11.7 ( 2.8) .492 ( 8.2) 531 9 (18.5) 9627 (22.0) 2.22 (12.2) Parallam PSL Avg (%cv) 101 11.5 ( 8.4) .558 ( 3.2) 6007 (17.1 ) 9578 (14.9) 2.07 ( 8.7) TABLE 4 B Moisture Content Adjusted to 12%* X n Moisture Content (%) Specific Gravity Propor 1nl Limit Stress (psi ) Modulus of Rupture (psi ) Modulus of Elasticity (10 psi) 1650F, 1.5E Douglas-fir Avg (%cv) 97 12.0 . 455 (8.5) 3760 (16.8) 7026 (31.2) 1 . 73 (16.1 ) 2400F, 2.0E Douglas-fir Avg (%cv) 92 12.0 .491 (8.1 ) 5280 (18.1 ) 9557 (21.8) 2.21 (12.1 ) Parallam PSL Avg (%cv) 101 12.0 .555 (3.5) 5934 (16.7) 9474 (15.5) 2.08 ( 8.9) (*) as per ASTM D2519 test methods TABLE 5A DEFORMATICM/RIJTTURE DATA FOR STRESS LEVEL 1 1650F DOUGLAS-FIR - 2060 psi 24OOF DOUGLAS-FIR -- 3000 p s i PAR? £1AM - 4000 ps i LOAD NO. OF DURATION DEFLECTION FRACTIONAL NO. OF DEFLECTION FRACTIONAL NO. OF DEFLECTION FRACTIONAL CREEP FAILURES CREEP FAILURES CREEP FAILURES (hr.) (in.) (in.) (in.) .02 .036 1.00 0 .041 1.00 0 .054 1.00 0 (1 minute) (17.4)** (16.5) (8.5) 28 .038 1.06 0 .044 1.06 0 .057 1.07 (18.3) (4.6) (19.6) (5.0) (9.6) (2.5) 0 100 .039 1.09 0 .045 1.10 0 .059 1.10 0 (19.7) (5.1) (22.6) (6.8) (10.5) (3.3) 288 .041 1.15 0 .048 1.18 0 .062 1.16 0 (20.7) (7.2) (25.5) (9.1) (11.5) (4.8) 529 .045 1.25 0 .050 1.25 1 .066 1.22 0 (22.4) (7.6) (15.4) (5.5) (12.5) (5.6) 1200 .046 1.28 0 .051 1.27 1 .067 1.25 0 (23.5) (8.7) (14.9) (5.3) (13.6) (6.4) 2325 .048 1.32 0 .053 1.32 1 .070 1.30 0 (24.7) (9.8) (15.5) (5.3) (14.9) (7.4) 3662 .050 1.37 0 .055 1.36 1 .071 1.33 0 (25.5) (10.8) (16.0) (5.9) (11.5) (6.3) 5568 .051 1.40 0 .056 1.38 1 .072 1.35 0 (25.8) (11.0) (15.9) (5.7) (11.4) (6.1) 7416 .052 1.43 0 .057 1.41 1 .073 1.37 o (27.2) (12.5) (15.6) (5.8) (11.2) (6.3) 11210 .054 1.47 0 .058 1.44 1 .075 1.40 1 (29.2) (14.3) (15.8) (6.3) (12.0) . (7.1) * 34 beams i n each stress level at loadup **%CV in brar:ke>-r=; TABLE 5B DEFRCMATIONffiUFTURE - DATA FOR STRESS LEVEL 2 165QF DOUGLAS-FIR -• 2325 psi 2400F DOUGLAS-FIR -• 3375 psi PARALLAM - 4500 psi LOAD DURATION (nr.) DEFLECTION (in.) FRACTIONAL CREEP NO. OF FAILURES DEFLECTION (in.) FRACTIONAL CREEP NO. OF FAILURES DEFLECTION (in.) FRACTIONAL CREEP NO. OF' FAILURES .02 (1 minute) .040 (13.0)** 1.00 0 .045 (13.4) 1.00 0 .059 (7.9) 1.00 0 28 .042 (13.5) 1.04 (2.6) 0 .047 (15.0) 1.06 (4.1) 0 .064 (7.8) .. 1.08 (2.7) 0 100 .043 (14.4) 1.07 (2.9) 0 .049 (16.1) 1.11 (4.9) 2 .066 (8.4) 1.11 (3.5) 0 288 .045 (14.6) 1.14 (3.7) 0 .052 (16.3) 1.17 (5.3) 2 .069 (8.6) 1.17 (3.9) 0 529 .050 (15.8) 1.25 (5.5) 0 .057 (17.6) 1.27 (6.2) 3 .073 (9.3) 1.23 (4.9) 0 1200 .051 (16.2) 1.26 (5.6) 0 .057 (14.8) 1.28 (6.0) 4 .074 (9.5) 1.26 (4.9) 0 2325 .053 (16.3) 1.32 (5.6) 0 .059 (15.5) 1.33 (7.0) 4 .077 (10.3) 1.31 (5.8) 0 3662 .055 (17.2) 1.37 (7.0) 1 .060 (16.1) 1.37 (6.3) 5 .080 (10.5) 1.35 (6.1) 0 5568 .056 (17.7) 1.40 (7.1) 1 .061 (16.2) 1.39 (6.6) 5 .081 (10.5) 1.37 (5.9) o 7416 11210 .056 (17.9) .058 (18.5) 1.42 (7.5) 1.46 (8.0) 1 1 .062 (15.9) .064 (16.8) 1.41 (6.4) 1.45 (7.2) 5 5 .082 (10.8) .084 ( H t 2) 1.39 (6.4) 1.42 ff5.7) 0 0 **%CV in brackets TAbfiF. 5C DEFORMAITION/RUPTORE DATA FOR STRESS LEVEL 3 * 1650F DOUGLAS-FIR - 2575 psi 2400F DOUGLAS-FIR - 3750 psi PARALLAM - 5000 psi LOAD DURATION DEFLECTION FRACTIONAL CREEP NO. OF FAILURES DEFLECTION FRACTIONAL CREEP NO. OF FAILURES DEFLECTION FRACTIONAL CREEP NO. OF FAILURES (hr.) (in.) (in.) (in.) .02 (1 minute) .045 (16.5)** 1.00 0 .051 (13.1) 1.00 0 .065 (8.1) 1.00 0 28 .047 (16.6) 1.06 (2.8) 0 .054 (14.8) 1.06 (3.3) 0 .070 (8.8) 1.08 (2.8) 0 100 .049 (17.2) 1.09 (3.7) 0 .056 (15.0) 1.10 (4.2) 0 .073 (8.9) 1.11 (2.6) 0 288 .052 (17.7) 1.16 (4.7) 0 .059 . (15.6) 1.17 (5.0) 1 .076 (9.5) 1.16 (3.7) 0 529 .057 (19.4) 1.27 (6.4) 0 .063 (16.4) 1.26 (5.8) 1 .080 (10.2) 1.23 (4.5) 0 1200 .059 (21.5) 1.31 (7.8) 1 .065 (18.9) 1.29 (7.4) 2 .082 (10.4) 1.25 (5.0) 0 2325 .060 (21.1) 1.36 (8.6) 4 .065 (16.2) 1.32 (7.4) 4 .086 (10.8) 1.31 (5.4) 0 3662 .062 (22.1) 1.41 (9.6) 4 .068 (15.7) 1.37 (7.3) 4 .088 (11.2) 1.35 (6.0) 0 5568 .063 (22.0) 1.44 (9.7) 4 .069 (16.0) 1.39 (7.5( 4 .090 (11.5) 1.37 (6.3) 0 7416 .065 (22.7) 1.47 (10.5) 4 .070 (16.6) 1.42 (8.1) 4 .091 (12.0) 1.40 (6.8) 0 11210 .067 (24.4) 1.52 (12.0) 4 .072 (16.7) 1.46 (8.2) 4 .093 (12.6) 1.42 (7.8) 0 *34 beams in each stress level holdup **%CV in brackets TABLE 6 DURATION OF LOAD STUDY - TIME TO FAILURE DATA Rank Percent S u r v i v a l TIME TO FAILURE, HOUR STRESS LEVEL 1 1650f D . - f i r 2400f D . - f i r 3200f Parallam STRESS LEVEL 2 1650f D . - f i r 2400f D . - f i r 3200f Parallam STRESS LEVEL 3 1650f D . - f i r 2400f D . - f i r 3200f Parallam 1 97.1 2 94.1 3 91.2 4 88.2 5 85.3 6 82.4 7 79.4 8 76.5 9 73.5 10 70.6 11 67.6 12 64.7 13 61.8 14 58.8 15 55.9 16 52.9 17 50.0 18 47.1 19 44.1 20 41.2 21 38.2 22 35.2 23 32.4 24 29.4 25 26.5 26 23.5 27 20.6 28 17.6 29 14.7 30 11.8 31 8.8 32 5.9 33 2.9 34 0.0 333 10958 2784 74 74 453 861 3280 1104 1368 1368 2016 240 1 024 2112 2280 157 TABLE 7A CURVE FIT PARAMETERS - 1650F.1.5E D o u g l a s - f i r STRESS LEVEL 1 NO. MOEt (E6 D5i) POWER MODEL A r (E-02) 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 26 27 28 29 30 31 32 33 34 1.436 1.18 1.337 1.282 1.437 1.371 1.288 1.227 1.467 1.52 1.553 1.593 1.552 1.746 1.688 1.846 1.685 1.688 1.65 1.561 1.749 1.96 1.692 1.743 2.013 1.725 2.045 1.79 1.845 2.043 2.192 1.983 2.202 2.388 AVERAGE CURVE SUMMARY STATISTICS MEAN 1.691 STD. DEV. 0.291 X CV 17.2 N 34 0.214 0.488 0.411 0.367 0.403 0.446 0.317 0.382 0.413 0.349 0.451 0.462 0.434 0.317 0.356 0.212 0.284 0.386 0.368 0.322 0.404 0.363 0.496 0.395 0.491 0.252 0.454 0.359 0.259 0.209 0.412 0.268 0.268 0.434 9.728 0.625 1.918 2.505 0.854 0.97 3.194 4.017 0.805 2.76 0.796 0.524 1.052 1.96 2.472 6.688 3.303 1.048 1.898 2.539 1.26 0.915 0.732 0.989 0.482 2.713 0.457 1.466 2.785 8.102 0.629 3.802 4.587 1.287 0.991 0.95 0.958 0.971 0.979 0.937 0.986 0.995 0.96 0.962 .0.963 0.944 0.927 0.957 0.966 0.972 0.979 0.911 0.969 0.942 0.95 0.963 0.965 0.854 0.922 0.989 0.881 0.968 0.943 0.974 0.947 0.975 0.986 0.962 b l (E-02) 4.446 4.984 4.427 4.698 4.134 4.277 4.746 5.078 4.018 3.972 3.849 3.693 3.781 3.459 3.593 3.305 3.641 3.481 3.652 3.481 3.381 3.024 3.494 3.329 3.018 3.467 2.861 3.366 3.268 3.028 2.732 3.1 2.832 2.498 4-par. b2 (E-02) 1.658 1.427 2.027 1.876 0.952 1.568 1.339 2.712 0.835 1.516 1.079 0.761 1.322 0.729 1.257 0.879 0.976 0.793 1.143 1.146 1.045 0.405 1.19 0.645 0.8 0.464 0.438 0.5075 0.52 0.844 0.491 0.688 0.814 0.834 VISCOELASTIC b3 b4 (E-03) (E-07) 3.385 2.39 2.529 2.514 1.023 1.558 3.075 2.35 2.134 2.899 1.574 2.011 2.581 2.557 2.509 6.383 1.8 2.187 2.483 3.506 2.011 2.551 2.227 3.01 1.185 5.435 2.234 2.935 4.235 7.578 0.808 3.876 2.602 3.279 7.229 7.047 10.534 8.88 2.32 4.623 11.341 34.436 3.133 7.164 3.657 3.646 2.796 3.029 6.101 4.736 3.137 3.41 5.22 3.568 4.807 2.775 7.795 7.17 2.888 4.087 4.058 8.321 3.593 6.919 2.067 5.343 4.393 6.573 MODEL b5t »<b2/bl) 0.373 0.286 0.458 0.399 0.23 0.367 0.282 0.534 0.208 0.382 0.28 0.206 0.35 0.211 0.35 0.266 0.268 0.228 0.313 0.329 0.309 0.134 0.341 0.194 0.265 0.134 0.153 0.151 0.159 0.279 0.18 0.222 0.287 0.334 b6t (E-05) *(b4/bl) 1.626 1.414 2.379 1.89 0.561 1.081 2.39 6.781 0.78 1.804 0.95 0.987 0.739 0.876 1.698 1.433 0.862 0.98 1.429 1.025 1.422 0.918 2.231 2.154 0.957 1.179 1.418 2.472 1.099 2.285 0.757 1.724 1.551 2.631 0.357 1.934 0.979 3.667 1.034 2.497 6.216 0.282 1.695 0.366 0.082 22.4 34 2.349 2.151 91.6 34 0.956 0.03 3.1 34 3.65 0.639 17.5 34 1.049 0.5 47.7 34 2.806 1.377 49.1 34 6.082 5.453 89.7 34 0.278 0.092 33.1 34 1.602 1.067 66.6 34 158 TABLE 7B CURVE FIT PARAMETERS - 1650F.1.5E Douglas-fir STRESS LEVEL 2 POWER MODEL NO. MOEt B A r (E6 DSI) (E-02) I 1.54 0.301 0.761 0.949 2 1.354 0.327 3.239 0.982 3 1.444 0.5 0.148 0.957 4 1.401 0.481 0.764 0.95 5 1.542 0.451 0.843 0.955 6 1.615 0.293 2.547 0.94 7 1.388 0.433 0.855 0.945 S 1.48 0.396 1.97 0.986 9 1.409 0.362 2.31 0.971 10 1.55 0.461 0.945 0.917 11 1.434 0.451 1.208 0.965 12 1.76 0.26 3.312 0.989 13 1.613 0.457 0.745 0.951 14 1.812 0.451 0.868 0.972 15. 1.55 0 0 0 16 1.6 0.407 1.194 0.959 17 1.714 0.4 1.353 0.991 18 1.673 0.384 1.528 0.974 19 1.672 0.45 0.715 0.971 20 1.689 0.333 2.931 0.976 21 1.622 0.405 1.444 0.952 22 1.665 0.435 0.892 0.97 23 1.668 0.322 2.625 0.98 24 1.641 0.523 0.512 0.967 25 1.762 0.343 2.622 0.98 26 1.863 0.248 4.945 0.992 27 2.013 0.431 0.954 0.964 28 1.967 0.438 1.533 0.967 29 1.959 0.474 0.661 0.921 30 1.928 0.396 1.163 0.895 31 2.087 0.394 0.653 0.928 32 2.171 0.434 0.722 0.932 33 2.073 0.38 0.95 0.934 34 2.155 0.423 0.815 0.948 AVERASE CURVE 0.4 1.347 0.972 SUMMARY STATISTICS MEAN 1.719 0.403 1.508 0.959 STD. DEV. 0.229 0.066 1.055 0.023 X CV 13.3 16.4 70 2.4 N 31 31 31 31 bl (E-02) 4.424 5.066 4.649 4.844 4.32 4.101 4.749 4.666 4.78 4.25 4.709 3.969 4.097 3.757 4.3 4.22 4.087 4.063 4.011 4.108 4.195 4.071 4.091 4.101 3.887 3.742 3.305 3.435 3.364 3.462 3.232 3.087 3.201 3.116 4.034 4.001 0.529 13.2 31 4-Dar b2 (E-02! 0.908 1.765 1.241 1.5B5 1.157 0.97 1.131 1.86 1.672 1.59 1.816 0.829 1.106 1.042 1.25 1.004 1.411 1.181 0.856 1.431 1.267 1.045 1.01 1.47 1.183 0.903 0.838 1.619 0.977 1.081 0.472 0.728 0.52 0.643 1.121 1.148 0.35 30.5 31 VISCOELASTIC MODEL b3 b4 b5t b6t (E-03) (E-07! (E-05) *ib2/bli *(b4/bl) 1.724 -0.752 0.205 -0.177 2.535 9.422 0.348 1.86 L . / v 1 9.179 0.267 1.974 1.893 7.009 0.327 1.447 2.465 6.617 0.26B 1.532 2.855 4.945 0.237 1.206 2.653 8.732 0.23S 1.839 1.424 9.301 0.399 1.993 2.671 8.612 0.35 1.802 3.234 4.946 0.374 1.164 2.416 11.701 0.386 2.485 1.694 2.846 0.209 0.717 2.442 4.913 0.27 1.199 1.61 5.91 0.277 1.573 2.8 6 0.291 1.395 3.105 9.053 0.238 2.145 5.742 3.18! 0.345 0.778 2.01 5.485 0.291 1.35 2.526 6.69 0.213 1.666 2.587 6.65 0.348 1.619 3.422 9.709 0.302 2.314 1.533 4.648 0.257 1.142 3.273 8.476 0.247 2.072 1.003 6.628 0.358 1.616 2.976 • 9.143 0.304 2.352 4.381 6.924 0.241 1.85 2.78! 5.48 0.254 1.658 1.906 7.443 0.471 2.167 2.875 4.117 0.29 1.224 3.29 0.63 0.312 0.182 1.401 1.975 0.146 0.611 1.808 2.707 0.236 0.877 3.995 3.518 0.162 1.099 2.405 3.841 0.206 1.233 2.44 6.331 0.278 1.569 2.621 6.088 0.283 1.492 0.949 2.445 0.069 0,52 36.2 40.2 24.4 34.9 31 31 31 3! TABLE 7C CURVE FIT PARAMETERS - 1650F.1.5E Doualas-fir STRESS LEVEL 3 POWER MODEL NO. HOEt B A r <'E6 psi) (E-02) 1 1.312 0.33 2.086 0.981 i 1.437 0.418 3.182 0.988 7 1.135 0.725 0.228 0.969 4 1.336 0.465 0.743 0.955 r 1.577 0.433 1.192 0.855 6 1.366 0.319 3.522 0.989 1.564 0.405 1.167 0.985 8 1.537 0.514 0.668 0.948 9 1.476 0.502 0.629 0.956 10 1.566 0.4 1.664 0.995 1.572 0.479 0.737 0.945 12 1.577 0.412 0.938 0.937 ( 7 1.578 0.522 0.612 0.956 14 1.537 0.383 1.673 0.965 15 1.61 0.309 2.838 0.979 16 1.758 0.373 2.389 0.986 17 1.623 0.442 0.971 0.953 18 1.577 0.413 2.025 0.981 19 1.67 0.45 0.866 0.939 20 2.234 0.285 2.789 0.958 21 1.691 0.312 3.542 0.983 22 1.897 0.345 2.59 0.972 23 1.61 0.512 0.509 0.972 24 1.308 0.391 3.548 0.991 25 1.851 0.428 0.94 0.962 26 2.053 0.356 1.701 0.946 1*1 LI 1.941 0.326 2.529 0.965 28 2.082 0.322 3.243 0.964 29 1.815 0.459 0.48! 0.97 30 1.857 0.372 2.24 0.979 31 2.238 0.299 2.486 0.964 32 2.016 0.42 1.577 0.968 33 2.177 0.3 3.498 0.9B1 34 2.026 0.26 3.169 0.973 bl (E-02) 5.726 5.331 6.449 5.53 4.789 5.628 4.698 4.775 4.985 4.699 4.671 4.695 4.721 4.868 4.768 4.366 4.639 4.856 4.387 3.35 4.564 3.981 4.604 6.015 4.049 3.637 3.895 3.691 4.125 4.193 3.357 3.747 3.492 3.825 4-b2 (E-02) 1.348 2.321 12.975 1.557 141.063 1.913 0.329 1.697 1.427 37.997 1.381 1.005 1.876 1.415 1.307 1.648 1.406 2.302 1.315 0.748 1.553 1.319 1.146 3.632 1.027 0.972 1.08 1.215 0.734 1.517 0.703 1.441 0.994 0.772 Dar . VISCOELASTIC b3 b4 (E-03) (E-07) 2.457 3.246 0.0588 1.811 •0.00000 2.324 30.955 2.51 2.765 44.108 3.043 3.813 1.59 2.761 2.057 1.741 1.891 1.644 2.766 3.968 2.468 2.756 2.144 1.803 1.97 2.584 2.609 3.14 1.411 2.203 3.633 2.301 3.533 2.308 6.983 50.577 -7168.6 8.368 196.193 11.567 68.718 11.339 11.238 116.202 8.598 5.802 6.584 8.371 5.141 9.402 7.137 11.432 5.127 3.318 7.739 7.717 10.166 28.257 4.801 3.66 6.254 7.76 3.814 8.799 4.408 8.477 6.712 2.859 MODEL b5t Kb2/bl) 0.235 0.435 2.012 0.282 29.456 0.34 0.07 0.355 0.286 8.086 0.296 0.214 0.397 0.291 0.274 0.377 0.303 0.474 0.3 0.223 0.34 0.331 0.249 0.604 0.254 0.267 0.277 0.329 0.178 0.362 0.209 0.385 0.285 0.202 b6t (E-05) t(b4/bl) 1.22 9.487 -1111.58 1.513 40.967 2.055 14.627 2.375 2.254 24.729 1.841 1.236 1.395 1.72 1.078 2.153 1.538 2.354 1.169 0.99 1.696 1.938 2.208 4.698 1.186 1.006 1.606 2.102 0.925 2.098 1.313 2.262 1.922 0.747 AVERAEE CURVE 0.371 1.911 0.977 4.451 1.378 2.364 8.222 0.31 1.847 SUMMARY STATISTICS MEAN 1.735 0.39 1.915 0.966 4.453 1.395 2.483 7.994 0.308 1.745 STD. DEV. 0.272 0.076 1.062 0.015 0.696 0.561 0.661 4.558 0.086 0.735 1 CV 15.7 19.5 55.5 1.6 15.6 40.2 26.6 57 27.9 42.1 N 29 29 29 29 29 29 29 29 29 29 160 TABLE 8A CURVE FIT PARAMETERS - 2400F,2.0E Doualas-fir STRESS LEVEL 1 1 2 3 4 C J 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 MOEt (E6 psi) 1,332 1.755 1.951 1.842 1.917 2 1.898 1.651 1.713 1.985 2.131 1.857 1.947 2.041 1.952 2.313 2.192 2.226 2.21 2.523 2.384 2.262 2.426 1.989 2.267 2.315 2.314 2.725 2.441 2.597 2.5 2.466 2.46 2.96 POWER MODEL A r (E-02) 0.393 0.389 0.384 0.467 0.333 0.37 0.341 0.436 0.387 0.36 0.42 0.368 0.451 0.404 0.324 0.155 0.3 336 316 429 247 0.43 0.331 0.392 0.323 0.331 0.345 0.221 0.246 0.263 0.298 0.34 0.34 0.307 0.202 1.491 1.29 0.651 3.235 1.735 2.556 1.267 1.239 2.175 1.373 1.62 O.B 1.613 2.084 11.886 2.989 2.409 3.111 0.B24 6.791 0.793 1.938 1.321 1.549 1.63 1.694 5.546 2.701 4.088 2.933 2.353 2.15 2.873 1 0.959 0.911 0.969 0.946 0.968 0.971 0.956 0.978 0.915 0.973 0.975 0.955 0.974 0.973 0.982 0.971 0.962 0.949 0.97 0.964 0.96 0.987 0.988 0.968 0.976 0.955 0.976 0.921 976 92B 981 984 969 bl (E-02) 5.897 5.456 4.457 4.758 4.598 4.384 4.599 5.233 5.051 4.281 4.134 4.782 4.435 4.29 4.594 3.752 3.989 3.99 3.975 3.826 3.803 3.806 3.709 4.364 3.872 3.769 3.741 3.369 3.542 3.436 3.408 3.573 3.691 2.954 4-oar. b2 (E-02) 1.039 1.752 VISCOELASTIC b3 b4 (E-03) (E-07) 1.072 1.191 1.929 1.346 1.54 2.026 1.109 1.577 1.292 1.243 1.228 1.491 0.92 1.141 1.017 1.161 1.432 0.865 1.329 0.829 0.836 0.966 0.598 0.666 0.82 0.81 0.588 0.881 0.91 0.919 0.891 0.796 0.422 1.975 2.865 .458 .881 .961 .533 .156 2.552 4.087 2.633 2.277 1.916 1.984 3.466 2.147 3.345 2.774 2.784 2.095 3.51 2.508 1.599 2.404 2.255 2.364 3.004 2.738 4.634 2.6B7 3.389 3.4 2.546 3.458 327.126 7.91 4.003 5.594 5.193 4.257 6.405 8.421 7.769 4.55 10.453 5.984 4.637 7.605 6.988 7.064 6.139 5.226 3.37 4.369 7.53 4.719 3.981 9.298 4.34 4.617 4.769 3.072 1.7 3.818 8.35 7.438 6.546 4.214 MODEL b5t I(b2/bl) 0.176 0.321 0.241 0.25 0.42 0.307 0.335 0.387 0.22 0.368 0.313 0.26 0.277 0.348 0.2 0.304 0.255 0.291 0.36 0.226 0.349 0.218 0.225 0.221 0.154 0.177 0.219 0.24 0.166 0.256 0.267 0.257 0.241 0.269 b6t (E-05) Mb4/bl) 55.473 1.45 0.B9S 1.176 1.129 0.971 1.393 1.609 1.538 1.063 2.529 1.251 1.046 1.773 1.521 1.883 1 539 1.31 0.848 1.142 1.98 1.24 1.073 2.131 1.121 1.225 1.275 0.912 0.48 1.111 2.45 2.082 1.774 1.427 AVERAGE CURVE 0.335 2.239 0.977 4.1 1.101 2.748 5.877 0.269 1.433 SUMMARY STATISTICS MEAN 2.188 0.345 2.506 0.964 4.11 1.126 2.678 5.768 0.271 1.405 STD DEV. 0.303 0.068 2.098 0.02 0.564 0.357 0.688 1.951 0.064 0.459 1 CV 13.8 19.7 83.7 2.1 13.7 31.7 25.7 33.8 23.6 32.7 N 33 33 33 33 33 33 33 33 33 33 161 TABLE 8B CURVE FIT PARAMETERS - 2400F.2.0E Do u g l a s - f i r STRESS LEVEL 2 POWER MODEL NO. MOEt B A r bl (E6 PSI! (E-02! (E-02; 1 1.636 0.407 0.217 0.993 5.897 2 1.8 0.43 1.136 0.967 5.456 3 1.928 0.336 1.95B 0.952 5.555 4 1.923 0.416 1.263 0.98 5.102 5 2.007 0 0 0 4.8 6 1.85 0.328 2.177 0.986 5.333 7 2.01 0 0 0 4.8 S 1.921 0.289 2.085 0.933 5.08 9 2.055 0.423 0.905 0.938 4.686 10 2.344 0.249 4.578 0.964 4.279 11 1.897 0.302 4.995 0.979 5.394 12 1.97 0.31 2.72 0.977 5.039 13 2.003 0.534 0.419 0.889 4.743 14 2.271 0 0 0 4.4 15 1.983 0.175 11.385 0.971 5.087 16 2.107 0.22 6.242 0.979 4.786 17 2.087 0.334 2.112 0.95 4.652 IS 2.158 0.315 2.381 0.984 4.608 19 2.089 0.366 2.459 0.977 4.755 20 2.193 0.476 0.636 0.96 4.389 21 2.236 0.359 1.914 0.956 4.342 22 2.187 0.266 4.155 0.959 4.538 23 2.244 0.407 1.644 0.936 4.212 24 2.561 0.347 2.657 0.926 3.812 25 2.953 0.32 1.901 0.91 3.37! 26 2.37 0.379 1.485 0.983 4.17 27 2.244 0.484 0.628 0.962 4.304 28 2.38 0.461 0.685 0.965 4.096 29 2.252 0.416 0.375 0.996 4.379 30 2.496 0.344 2.398 0.95 4.058 31 2.296 0.34 2.012 0.966 4.361 32 2.539 0.398 0.956 0.959 3.896 33 3.104 0.22 6.364 0.984 3.277 34 2.969 0.38 1.031 0.983 3.356 AVERAGE CURVE 0.335 2.295 0.975 4.496 SUMMARY STATISTICS MEAN 2.237 0.352 2.596 0.962 4.508 STD. DEV. 0.33 0.082 2.27 0.024 0.609 1 CV 14.8 23.3 87.4 2.5 13.5 N 29 29 29 29 29 4-b2 (E-02) 1.039 1.752 1.191 1.318 -13.243 1.248 1.8412 0.864 1.052 1.259 2.479 1.257 1.459 1.25 1.72 Dar . VISCOELASTIC b3 b4 (E-03) (E-07) 1.158 1.176 1.012 1.913 1.098 1.295 1.246 1.552 1.48 0.696 1.021 1.175 0.935 0.893 1.308 1.104 0.894 0.871 0.654 1.227 1.248 0.372 29.8 29 4.219 1.975 3.669 1.746 0.407 2.334 4.073 3.094 3.876 2.31 2.113 2.85 1.936 2.8 9.779 5.641 3.665 2.795 1.839 2.581 2.97 3.45 3.278 3.921 2.927 2.181 2.128 2.678 7.951 3.423 3.099 1.137 3.13 1.417 327.127 7.91 6.122 13.513 5.354 7.421 6.05 4.486 6.439 1.627 8.347 7.053 6.628 6 8.374 8.375 5.665 7.156 7.014 7.019 5.276 5.618 12.2351 4.875 2.116 6.974 6.443 7.042 65.105 5.263 5.269 1.284 3.768 2.488 MODEL b5* »(b2/bl) 0.176 0.321 0.214 0.258 -2.759 0.234 0.384 0.17 0.224 0.294 0.46 0.249 0.308 0.284 0.338 0.242 0.253 0.22 0.402 0.25 0.298 0.275 0.368 0.388 0.206 0.245 0.273 0.228 0.204 0.322 0.253 0.229 0.266 0.195 b6t (E-05) K b 4 / b l ) 55.473 1.45 1.102 2.649 1.115 1.392 1.26 0.883 1.374 0.38 1.547 1.4 1.397 1.364 1.646 1.75 1.218 1.553 1.475 1.599 1.215 1.238 2.905 1.279 0.628 1.672 1.497 1.719 14.868 1.297 1.208 0.33 1.15 0.741 2.83 6.452 0.273 1.435 3.032 1.559 51.4 29 6.269 2.641 42.1 29 0.275 0.065 23.6 29 1.369 0.527 38.5 29 TABLE 8C CURVE FIT PARAMETERS - 2400F.2.0E Douglas-fir STRESS LEVEL 3 POWER MODEL NO. MOEt B A r (E6 Dsi) (E-02) 1 1.696 0 9.528 0 1 L 1 • 555 0.438 2.482 0.989 3 1.82 0.425 0.803 0.942 4 2.057 0.462 1.622 0.998 5 1.847 0.337 2.995 0.991 4 2.013 0.446 1.252 0.978 7 2.094 0.42 0.473 0.957 8 2.069 0.421 1.282 0.963 9 1.941 0.352 2.405 0.982 10 2.104 0.445 1.366 0.954 11 2.283 0.268 2.781 0.978 12 1.902 0.345 2.997 0.955 13 1.989 0.246 5.223 0.979 14 2.078 0.337 2.091 0.989 15 1.99 0.306 2.856 0.995 16 2.144 0.322 3.468 0.968 17 2.266 0.289 4.262 0.981 18 1.749 0.315 3.505 0.976 19 2.227 0.218 8.717 0.993 20 2.102 0.356 2.533 0.955 21 2.25 0.301 2.307 0.991 22 2.241 0.484 0.586 0.946 23 2.445 0.272 3.397 0.98 24 2.286 0.371 1.24 0.985 25 2.4 0.409 1.302 0.889 26 2.277 0.278 3.387 0.978 27 2.281 0.293 3.018 0.963 28 2.433 0.391 1.008 0.907 29 2.452 0.474 0.776 0.95 30 2.429 0.291 2.944 0.953 31 2.284 0.325 2.589 0.975 32 2.471 0.356 1.281 0.962 33 2.586 0.302 1.945 0.983 34 2.93 0.406 1.181 0.942 bl (E-02) 6.297 6.978 5.895 5.2 6.048 5.507 5.114 5.207 5.6 5.116 4.795 5.917 5.61 5.431 5.574 5.122 4.991 6.358 5.172 5.268 4.926 4.76 4.453 4.804 .398 .853 .772 .366 .388 4.474 4.995 4.44 4.256 3.704 4-b2 (E-02) 0.604 1.262 1.268 0.501 1.985 344.496 0.606 1.582 1.434 2.239 0.817 2.507 1.531 1.46 1.288 1.905 1.651 2.285 1.719 1.93 0.904 1.244 0.891 0.882 1.414 1.163 1.193 1.109 1.359 1.15 1.673 0.737 0.653 0.962 oar. VISCOELASTIC b3 b4 (E-03) (E-07) 232.876 1.741 2.728 4.098 1.964 0.108 2.291 3.162 4.046 2.466 4.153 2.737 3.972 1.096 2.808 3.234 2.837 2.061 3.625 3.311 2.609 2.83 8.293 1.643 3.507 2.838 4.328 2.009 2.598 3.488 1.175 3.133 4.33 3.498 -1.236 229.852 7.253 207.815 13.823 •3372.54 3.632 11.348 18.616 10.218 5.842 7.723 8.228 4.634 10.151 9.146 8.392 9.207 9.106 9.621 6.814 6.679 8.944 6.778 8.397 6.051 6.438 2.32 7.147 4.217 2.966 6.38 5.585 5.248 MODEL b5t I(b2/bl) 0.096 0.181 0.215 0.096 0.328 62.556 0.118 0.304 0.256 0.438 0.17 0.424 0.273 0.269 0.231 0.372 0.331 0.359 0.332 0.366 0.184 0.261 0.2 0.184 0.322 0.24 0.25 0.254 0.31 0.257 0.335 0.166 0.153 0.26 b6t (E-05) t(b4/bl) -0.196 32.94 1.23 39.964 2.286 -612.411 0.71 2.179 3.324 1.997 1.218 1.305 1.467 0.853 1.821 1.786 1.681 1.448 1.761 1.826 1.383 1.403 2.009 1.411 1.909 1.247 1.349 0.531 1.629 0.943 0.594 1.437 1.312 1.417 AVERAGE CURVE 0.326 2.492 0.977 5.029 1.365 2.843 7.915 0.271 1.574 SUMMARY STATISTICS MEAN 2.212 0.345 2.491 0.965 5.027 1.385 3.092 7.697 0.272 1.516 STD. DEV. 0.248 0.066 1.626 0.024 0.591 0.487 1.279 3.203 0.078 0.546 1 CV 11.2 19.1 65.3 2.5 11.8 35.2 41.4 41.6 28.7 36 N 30 30 30 30 30 30 30 30 30 30 TABLE 9A CURVE FIT PARAMETERS - Parallaa PSL STRESS LEVEL 1 POKER MODEL NO. MOEt E A r (E6 D5i) (E-02! 1 1.909 0.287 3.009 0.963 i L 1.972 0.263 3.538 0.975 3 1.833 0.31 3.656 0.989 4 2.042 0.232 5.079 0.994 c J 1.727 0.416 0.418 0.998 6 2.055 0.308 3.504 0.981 1 I 1.945 0.332 2.153 0.977 8 2.076 0.283 2.792 0.986 9 2.158 0.259 3.288 0.986 10 2.043 0.257 4.149 0.96 11 2.118 0.235 5.579 0.992 12 2.155 0.295 2.412 0.988 13 2.137 0.315 2.985 0.97 14 2.15 0.257 3.936 0.99 15 2.08B 0.266 4.856 0.992 16 2.022 0.339 2.444 0.987 17 2.008 0.486 0.415 0.982 18 2.195 0.277 3.817 0.988 19 2.2 0.309 2.57 0.981 20 2.122 0.312 2.304 0.984 21 2.199 0.335 2.164 0.978 22 2.113 0.284 3.175 0.989 23 2.197 0.35 2.469 ' 0.97 24 2.138 0.432 0.52 0.986 25 2.231 0.407 0.657 0.974 26 2.296 0.296 3.098 0.983 27 2.451 0.302 1.727 0.958 28 2.27 0.412 0.655 0.976 29 2.348 0.277 4.454 0.978 30 2.283 0.296 2.256 0.994 31 2.49 0.263 2.676 0.995 32 2.384 0.348 1.603 0.985 33 2.451 0.267 4.332 0.991 34 2.362 0.327 1.565 0.979 AVERAGE CURVE 0.298 2.783 0.989 SUMMARY STATISTICS MEAN 2.165 0.31 . 2.844 0.982 STD.DEV. 0.157 0.056 1.287 0.009 1 CV 7.3 18.1 45.3 0.9 N 33 33 33 33 4-oar. VISCOELASTIC MODEL bl b2 b3 b4 b5t b6t • (E-02) (E-02) (E-03) (E-07) I!b2/bl) (E-05) t(b4/bl! 0 . i O i 1.467 2.4 6.078 0.237 0.98 5.948 1.341 3.898 6.186 0.225 1.04 6.587 2.255 2.102 10.876 0.342 1.65! 5.919 1.364 2.394 6.029 0.23 1.019 6.883 2.037 5.451 90.996 0.296 13.22 5.302 1.926 2.484 8.612 0.332 1.484 6.066 1.488 1.988 8.45 0.245 1.393 5.67 1.134 2.51 6.607 0.2 1.165 5.463 1.075 3.016 5.395 0.197 0.988 5.732 1.475 4.378 6.589 0.257 1.15 5.625 1.395 4.749 9.413 0.248 1.673 5.425 1.005 3.199 6.885 0.185 1.269 5.546 1.734 2.582 6.654 0.313 1.2 5.501 1.182 3.244 7.743 0.215 1.408 5.836 1.784 2.138 7.959 0.306 1.364 5.83 1.455 3.374 1.486 0.25 0.255 5.764 1.426 0.775 1.054 0.247 0.183 5.396 1.365 2.988 8.526 0.253 1.58 5.332 1.215 3.027 7.723 0.228 1.448 5.518 1.19 2.954 7.039 0.216 1.276 5.304 1.3 2.806 8.249 0.245 1.555 5.547 1.206 3.661 8.835 0.217 1.593 5.304 1.665 3.167 10.697 0.314 2.017 5.339 0.642 2.115 6.766 0.12 1.267 5.135 0.743 2.204 4.218 0.145 0.821 5.138 1.264 3.163 8.021 0.246 1.561 4.874 0.879 0.668 2.525 0.18 0.518 5.037 0.744 2.152 4.496 0.148 0.893 5.158 1.599 3.823 8.833 0.31 1.712 5.136 0.908 2.383 6.045 0.177 1.177 4.747 0.724 2.461 4.874 0.153 1.027 4.913 0.999 2.034 5.939 0.203 1.209 4.896 1.245 3.317 8.783 0.254 1.794 4.862 0.795 3.166 5.431 0.164 1.117 5.474 1.245 2.771 7.412 0.227 1.354 5.471 1.272 2.767 6.758 0.23 1.236 0.419 0.363 0.847 2.259 0.055 0.401 7.7 28.5 30.6 33.4 23.9 32.4 33 33 33 33 33 33 TABLE 9B CURVE FIT PARAMETERS - Parallam PSL STRESS LEVEL 2 NO. HDEt <E6 psi) POWER MODEL A (E-02) 1 2 3 4 5 6 7 S 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 1.859 2.052 1.881 1.955 2.029 2.09 2.011 2.171 2.113 2.11 2.064 2.14 2.192 2.176 2.125 2.171 2.147 2.069 2.429 2.145 2.176 2.228 2.221 2.253 2.234 2.365 2.256 2.318 2.392 2.291 2.527 2.4 2.47 2.595 AVERAGE CURVE 0.386 0.301 0.295 0.259 0.274 0.268 0.296 0.259 0.271 0.371 0.278 0.327 0.275 0.292 0.237 0.32 0.271 0.373 0.164 0.322 0.334 0.256 0.295 0.266 0.296 0.301 0.346 0.287 0.332 0.284 0.297 0.336 0.235 0.22 0.286 SUMMARY STATISTICS MEAN 2.196 0.292 STD. DEV. 0.169 0.045 I CV 7.7 15.4 H 34 34 0.973 3.093 4.1 4.031 3.369 4.027 2.322 3.095 4.259 1.851 2.74 1.974 4.312 2.868 6.411 3.421 3.789 2.098 10.958 1.961 1.65 3.809 2.811 3.025 3.613 2.144 1.441 3.821 2.248 1.818 2.66 2.716 6.105 3.741 3.23 3.331 1.773 53.2 34 0.985 0.988 0.98 0.989 0.99 0.991 0.99 0.994 0.985 0.973 0.992 0.981 0.988 0.988 0.991 0.984 0.99 0.986 0.991 0.988 0.989 0.993 0.992 0.99 0.985 0.988 0.975 0.99 0.97 0.982 0.98 0.983 0.977 0.974 bl (E-02) 7.003 6.504 7.199 6.832 6.52 6.49 6.571 6.092 6.303 6.197 6.393 6.138 6.117 6.069 6.478 6.238 6.221 6.508 5.427 6.104 6.076 6.031 5.971 5.932 6.008 5.52 5.773 5.849 5.469 5.718 5.29 5.569 5.393 5.049 4-par b2 (E-02) 1.2 1.688 2.382 1.583 1.456 . VISCOELASTIC b3 b4 IE-03) (E-07) 1.624 1.215 1.077 1.686 1.859 1.201 1.396 1.721 1.245 1.909 2.147 1.464 2.175 1.575 1.116 1.28 1.267 1.293 1.171 1.744 0.977 4.044 1.667 1.374 0.6624 1.234 1.771 1.608 0.803 1.88 2.713 2.768 3.509 2.779 2.38 2.46 2.856 3.869 2.547 2.526 2.136 3.521 2.951 3.263 2.047 3.268 1.775 1.696 3.513 1.237 2.823 2.863 1.795 2.886 2.838 2.969 2.439 3.656 2.953 1.859 2.315 4.84 3.709 7.675 10.114 11.794 9.331 8.069 8.814 . 7.573 6.091 11.314 9.846 6.739 5.533 11.092 7.842 10.499 11.154 9.234 12.681 9.682 9.56 4.264 7.433 8.489 4.449 10.18 6.28 6.462 8.752 8.619 6.267 4.347 9.419 8.793 3.744 MODEL bS* *(b2/bl) 0.171 0.26 0.331 0.232 0.223 0.25 0.185 0.177 0.267 0.3 0.188 0.227 0.281 0.205 0.295 0.344 0.235 0.334 0.29 0.183 0.211 0.21 0.217 0.197 0.29 0.177 0.701 0.285 0.251 0.116 0.233 0.318 0.298 0.159 b6* (E-05) t(b4/bl) 1.096 1.555 1.638 1.366 1.238 1.358 1.152 1 1.795 1.589 1.054 0.901 1.813 1.292 1.621 1.788 1.484 1.949 1.784 1.566 0.702 1.232 1.422 0.75 1.694 1.138 1.119 1.496 1.576 1.096 0.822 1.691 1.63 0.742 0.99 6.095 1.447 2.844 8.358 0.237 1.371 0.986 0.006 0.6 34 6.09 0.481 7.9 34 1.547 0.572 37 34 2.754 0.73 26.5 34 8.298 2.262 27.3 34 0.262 0.1 38.2 34 1.372 0.363 26.5 34 TABLE 9C CURVE FIT PARAMETERS - Farallas PSL STRESS LEVEL 3 NO. MOEt (E6 psi) 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 26 27 28 29 30 31 32 33 34 2.025 1.936 2.064 1.968 2.008 2.041 2.04 1.999 2.06 2.129 2.076 2.038 2.139 2.103 2.149 2.315 2.082 2.075 2.178 2.245 2.31 2.213 2.309 2.239 2.314 2.347 2.27 2.396 2.415 2.516 2.388 2.606 2.606 2.522 0.275 0.28 0.194 0.292 0.306 0.259 0.308 0.317 0.33 0.343 0.326 0.439 0.295 0.27 0.286 0.271 0.314 0.305 0.357 .292 .301 .276 .286 .301 .219 .263 .337 0.285 0.315 0.31 0.291 0.299 0.281 0.281 POWER MODEL A (E-02) 4.993 3.511 7.008 3.831 2.311 3.666 2.008 3.243 3.398 1.807 2.289 0.666 3.21 3.141 4.221 4.564 2.761 2.95 1.561 3.41 2.587 4.402 2.612 2.429 6.667 3.63 1.385 4.002 1.493 2.304 2.629 2.672 2.23 4.426 4-oar. VISCOELASTIC MODEL 0.992 0.992 0.976 0.987 0.99 0.995 0.991 0.982 0.981 0.982 0.983 0.936 0.987 0.994 0.992 0.981 0.993 0.989 0.987 0.984 0.989 0.996 0.995 0.984 0.991 0.992 0.963 0.993 0.98 0.984 0.986 0.989 0.986 0.994 bl (E-02! 7.452 7.743 7.337 7.588 7.316 7.299 7.188 7.541 7.181 6.855 7.069 7.052 6.887 7.031 7.023 6.462 7.133 7.087 6.773 6.638 6.367 6.881 6.378 6.556 6.551 6.317 6.369 6.251 5.963 5.849 6.193 5 5.607 6.019 b2 (E-02! 1.888 1.724 2.225 1.477 1.508 1.275 2.452 2.528 1.513 1.721 1.236 1.697 1.398 2.118 1.972 1.762 1.705 1.527 1.693 7 1.369 1.985 1.097 1.228 1.658 1.362 1.103 1.733 0.79 1.193 1.258 1.342 0.851 1.841 b3 IE-03) 3.248 2.056 2.98 2.795 2.191 2.44 2.069 1.746 3.492 2.311 2.575 2.844 3.522 2.713 2.551 3.023 2.466 3.383 1.599 2.687 2.783 2.001 3.101 3.21 3.97 3.031 2.944 2.944 4.274 2.784 2.263 1.825 3.505 2.195 b4 (E-07) 17.355 9.669 6.038 13.639 8.351 8.539 7.96 11.533 18.764 8.685 9.917 8.672 11.765 7.973 12.836 9.124 12.625 13.041 7.317 11.395 8.509 10.745 9.502 10.12 10.829 7.819 4.919 11.932 6.611 7.696 7.147 5.721 6.005 9.842 b5» Kb2/bl! 0.304 0.244 0.235 0,293 0.202 0.207 0.177 0.325 0.352 0.221 0.243 0.175 0.246 0.199 0.302 0.305 0.247 0.241 0.225 0.255 0.215 0.288 0.172 0.187 0.253 0.216 0.173 0.277 0.132 0.204 0.203 0.235 0.152 0.306 bit (E-05) *(b4/bl) 2.329 1.249 0.823 1.797 1.141 1.17 1.107 1.529 2.613 1.267 1.403 1.23 1.708 1.134 1.828 1.412 1.77 1.84 1.08 1.717 1.336 1.562 1.49 1.544 1.653 1.238 0.772 1.909 1.109 1.316 1.154 1.004 1.071 1.635 AVERAGE CURVE SUMMARY STATISTICS MEAN 2.209 STD. DEV. 0.183 I CV B.3 N 34 0.29 3.165 0.991 6.759 0.297 0.04 13.5 34 3.177 1.344 42.3 34 0.986 0.011 1.1 34 6.755 0.556 8.2 34 1.609 1.603 0.415 25.9 34 .677 9.862 0.238 1.459 2.751 0.614 22.3 34 9.782 3.028 31 34 0.232 0.052 22.4 34 1.413 0.373 26.4 34 Appendix I STATISTICAL ANALYSES 167 DOL SURVIVORS FLEXURE RESULTS COMPARISON BETWEEN MEANS ANALYSIS OF VARIANCE - 1650F,1..5E DOUGLAS-FIR SOURCE FACTOR ERROR TOTAL LEVEL 1650_SL1 1650_SL2 1650 SL3 DF SS 2 1590755 94 459707776 96 461298528 N 34 33 30 POOLED STDEV MEAN 6860 7070 7166 2211 MS 795378 4890508 STDEV 2351 2066 2203 F 0.16 INDIVIDUAL 95 PCT CI 'S FOR MEAN BASED ON POOLED STDEV ( A ) ( A ) ( A ) 6600 7200 7800 ANALYSIS OF VARIANCE - 2400F,2.0E DOUGLAS-FIR SOURCE FACTOR ERROR ~^TAL LEVEL 2400_SL1 2400 SL2 2400 SL3 DF SS 2 6852639 89 388132192 91 394984832 N 33 29 30 POOLED STDEV MEAN 9625 9179 9849 2088 MS 3426319 4361036 F 0.79 INDIVIDUAL 95 PCT C I ' S FOR MEAN BASED ON POOLED STDEV STDEV + + +--• 2351 ( A ) 1929 ( * ) 1921 ( * 9000 9600 10200 ANALYSIS OF VARIANCE - PARALLAM PSL SOURCE FACTOR ERROR TOTAL LEVEL PSL_SL1 PSL_SL2 PSL SL3 DF 2 98 1 0 0 N 33 34 34 SS 3131017 211393792 214524816 MEAN 9415 9712 9295 MS 1565509 2157079 F 0. 73 D00LED STDEV - 1 4 6 9 INDIVIDUAL 95 PCT CI 'S FOR MEAN BASED ON POOLED STDEV STDEV -+ + + + 1435 ( * ) 1370 ( * ) 1592 ( * ) 8800 9200 9600 10000 FRACTIONAL CREEP RESULTS - COMPARISON BETWEEN STRESS LEVEL MEANS :A68 ANALYSIS OF VARIANCE - 1650F,1.5E DOUGLAR-FIR ;SOURCE FACTOR' ERROR TOTAL LEVEL 1650 S L l 1650 SL2 1650 SL3 DF 2 91 93 N 34 31 29 SS 0.0542 2.SI 94 2.87 36 MEAN .4685 . 4629 . 5176 MS" 0.0271 0.0310 STDEV 0.2104 0.1178 0.1834 POOLED STDEV = 0.1760 F 0 . 87 INDIVIDUAL 95 PCT CI 'S FOR MEAN BASED ON POOLED STDEV ( A ) ( * ) ( * ) 1.450 1.500 1.550 ANALYSIS OF VARIANCE - 2400F,2.0E DOUGLAS-FIR SOURCE FACTOR ERROR TOTAL LEVEL 2400 S L l 2400 SL2 2400 SL3 DF 89 91 M 33 29 30 POOLED STDEV = S S 0 . 0055 0.9863 0 . 9918 MEAN 1.4409 I .4469 I.4593 0.1053 MS 0.0027 0.0111 STDEV 0.0908 0.1057 0.1188 p 0.25 INDIVIDUAL 95 PCT C I ' S FOR MEAN BASED ON POOLED STDEV ( A ) ( * ) ( * ) 1.410 1.440 1.470 1.500 ANALYSIS OF VARIANCE PARALLAM PSL SOURCE FACTOR ERROR TOTAL LEVEL PSL S L l PSL SL2 PSL SL3 DF 9 7 99 N 34 33 POOLED STDEV SS 0.01202 0 . 95200 0.96402 MEAN 1.4045 1.4215 1.. 4312 0 . 0991 MS 0.00601 0 . 00981 STDEV 0.0998 0.0962 0.1012 F 0.61 INDIVIDUAL 95 PCT CI 'S FOR MEAN BASED ON POOLED STDEV ( * ) ( * ) ( * ) 1.380 1.410 1.440 1.470 169 . FRACTIONAL CREEP RESULTS --COMPARISON BETWEEN TEST MATERIALS (STRESS LEVELS COMBINED) ANALYSIS OF VARIANCE . SOURCE FACTOR ERROR TOTAL LEVEL 1650F DF 2400F DF PARALLAM DF 2 283 285 N 94 92 100 POOLED STDEV SS 0.1906 4.8294 5.0199 MEAN 1.4818 1.4488 1.4191 0.1306 MS 0.0953 0.0171 F 5. 58 INDIVIDUAL 9 5 PCX CI'S FOR MEAN BASED ON POOLED STDEV STDEV + + + + _ 0.1758 ( * , 0.1044 ( * , 0.0987 ( * ) | j. . j . 1.408 1.440 1.472 1.504 170 D U N C A N ' S M U L T I P L E RANGE T E S T - C A L C U L A T I O N S When t h i s procedure i s c a r r i e d out, the f o l l o w i n g t a b l e i s generated: p 2 3 r p 2.77 2.92 Rp 0.037 0.039 To d e t e r m i n e i f t h e f r a c t i o n a l c r e e p means a r e s i g n i f i c a n t l y d i f f e r e n t , t h e l e a s t s i g n i f i c a n t range v a l u e Rp (a=0.05) must be l e s s t h a n t h e d i f f e r e n c e between adjacent means, i.e.: a. X ( P a r a l l a m ) - X ( 2 4 0 0 F DF) = 0.03 <R2, t h e r e f o r e we c o n c l u d e t h a t X ( P a r a l l a m - X ( 2 4 0 0 F DF) a r e n o t s i g n i f i c a n t l y d i f f e r e n t . b. x"(Parallam)-X(1650F DF) = 0.06 >R3, t h e r e f o r e we c o n c l u d e t h a t X ( P a r a l 1 am-X(16 5 0F DF) a r e s i g n i f i c a n t l y d i f f e r e n t . c. X(2400F DF)-X(1650F DF) = 0.03 < R2, t h e r e f o r e we c o n c l u d e t h a t X~(2400F DF) and X(1650F DF) a r e not s i g n i f i c a n t l y d i f f e r e n t . The above c o n c l u s i o n s a r e t y p i c a l l y summarized by d r a w i n g a l i n e under any s u b s e t of a d j a c e n t means t h a t a r e not s i g n i f i c a n t l y d i f f e r e n t as shown below: 1650F 2400F P a r a l l a m F r a c t i o n a l Creep, Cf 1.48 1.45 1.42 Appendix SHEAR-FREE MODULUS OF ELASTICITY RESULTS (t = 1 minute) 172 TABLE II-1 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 1 Creep Data at t = 1 min. Beam j D e f l e c t i o n ( d t ) , i n . j MOE 1,000,000 p s i No. | D.Fir D.Fir Parallam | D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL | 1650f 1.5E 2400f 2.0E PSL Stress p s i ! Stress p s i 2060 3000 4000 | 2060 3000 4000 1 | 0.041 0. 064 0.060 | 1. 436 1.332 1.909 2 I 0.050 0.049 0.058 | 1. 180 1.755 1.972 3 | 0.044 0.044 0.063 | 1.337 1.951 1.833 4 I 0.046 0.047 0.056 | 1.282 1.842 2.042 5 I 0.041 0.045 0.067 | 1.437 1.917 1.727 6 • | 0.043 0.043 0.056 | 1.371 2.000 2.055 7 1 0.046 0.045 0.059 | 1.288 1.898 1.945 8 0.048 0.052 0.055 | 1.227 1.651 2.076 9 1 0.040 0.050 0.053 | 1.467 1.713 2.158 10 0.039 0.043 0.056 | 1.520 1.985 2.043 11 1 0.038 0.041 0.054 | 1. 553 2.131 2.118 12 0.037 0. 047 0.053 | 1.593 1.857 2.155 13 0.038 0. 044 0.054 | 1.552 1.947 2.137 14 0.034 0.042 0.053 | 1. 746 2.041 2.150 15 0.035 0.045 0.055 | 1.688 1.952 2.088 16 0.032 0.037 0.057 | 1.846 2.313 2.022 17 0.035 0.039 0.057 | 1.685 2.192 2.008 18 0.035 0.039 0.052 | 1.688 2.226 2.195 19 0.036 0.039 0.052 | 1.650 2.210 2.200 20 0.038 0.038 0.054 | 1.561 2.253 2.122 21 0.034 0.036 0.052 | 1.749 2.384 2.199 22 0.030 0.038 0.054 | 1. 960 2.262 2.113 23 0.035 0.036 0.052 | 1.692 2.426 2.197 24 0.034 0.043 0.053 | 1. 743 1.989 2.138 25 0.030 0.038 0.051 | 2.013 2.267 2.231 26 0.034 0.037 0.050 | 1. 725 2.315 2.296 27 0.029 0.037 0.047 | 2.045 2.314 2.451 28 0.033 0.032 0.050 | 1. 790 2.725 2.270 29 0.032 0.035 0.050 | 1.845 2.441 2.348 30 0.029 0.033 0.050 | 2. 043 2.597 2.283 31 0.027 0.035 0.046 | 2.192 2.500 2.490 32 0.030 0.035 0.048 | 1.983 2.466 2.384 33 0. 027 0.036 0.047 | 2. 202 2.460 2.451 34 0.025 0.029 0.048 | 2.388 2.960 2.362 S t a t i s t i c a l Data: Mean 0.036 0.041 0.054 | 1.691 2.155 2.152 CV% 17.4 16.5 8.5 | 17.5 15.4 8.1 n 34 34 34 | 34 34 34 Range | Low 0.025 0.029 0.046 | 1.180 1.332 1.727 High 0.050 0.064 0.067 | 2. 388 2.960 2.490 TABLE n _ 2 173 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Creep Data at t = 1 min. Beam D e f l e c t i o n ( d t ) , i n . | MOE 1,000,000 p s i No. | D.Fir D.Fir Parallam | D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL | 1650f 1.5E 2400f 2. 0E PSL Stress p s i 1 Stress p s i 2325 3375 4500 | 2325 3375 4500 1 | 0.043 0. 059 0.069 | 1. 540 1.636 1.859 2 I 0.049 0.054 0.063 | 1.354 1.800 2.052 3 1 0.046 0.050 0.069 | 1.444 1.928 1.881 4 1 0.048 0.050 0.066 | 1.401 1.923 1.955 5 I 0.043 0. 048 0.063 | 1.542 2.007 2.029 6 j 0.041 0.052 0.062 | 1.615 1.850 2.090 7 j 0.048 0. 048 0.064 [ 1.388 2.010 2. 011 8 I 0.045 0.050 0.059 [ 1.480 1.921 2.171 9 j 0.047 0. 047 0.061 | 1.409 2.055 2.113 10 | 0.043 0.041 0.061 | 1.550 2.344 2.110 11 1 0.047 0.051 0.062 | 1.434 1.897 2.064 12 | 0.038 0.049 0.060 | 1. 760 1.970 2.140 13 | 0.041 0.048 0.059 | 1.613 2.003 2.192 14 | 0.037 0. 044 0.059 | 1.812 2.271 2.176 15 | 0.043 0.049 0.061 | 1. 550 1.983 2.125 16 | 0.042 0.046 0.060 | 1.600 2.107 2.171 17 j 0.039 0.046 0.060 | 1. 714 2.087 2.147 18 | 0. 040 0.045 0.063 | 1.673 2.158 2.069 19 | 0.040 0. 046 0.053 | 1.672 2.089 2.429 20 | 0.040 0.044 0.060 | 1.689 2.193 2.145 21 | 0.042 0.043 0.059 | 1.622 2.236 2.176 22 | 0.040 0. 044 0.058 | 1.665 2.187 2.228 23 0.040 0.043 0.058 | 1.668 2.244 2.221 24 | 0.041 0. 038 0.057 | 1.641 2.561 2.253 25 | 0.038 0.033 0.058 | 1. 762 2.953 2.234 26 j 0.036 0.041 0.054 | 1.863 2. 370 2.365 27 | 0.033 0.043 0.057 | 2. 013 2.244 2.256 28 | 0.034' 0.041 0.056 | 1.967 2.380 2.318 29 | 0.034 0. 043 0.054 | 1.959 2.252 2.392 30 | 0.035 0. 040 0.056 | 1.928 2.496 2.291 31 I 0.032 0.043 0.051 | 2. 087 2.296 2.527 32 | 0.031 0.038 0.054 | 2.171 2.539 2.400 33 | 0.032 0.031 0.052 | 2. 073 3.104 2.470 34 | 0.031 0. 033 0.049 | 2.155 2.969 2.595 S t a t i s t i c a l Data: Mean | 0.040 0. 045 0.059 | 1. 700 2.208 2.196 CV% | 13.0 13.4 7.9 | 13.6 15.0 7.8 n j 34 34 34 | 34 34 34 Range | | Low | 0.031 0.031 0.049 | 1. 354 1.636 1.859 High | 0.049 0.059 0.069 | 2.171 3.104 2.595 TABLE II-3 174 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 3 Creep Data at t = 1 min Beam j D e f l e c t i o n ( d t ) , i n . | MOE 1 ,000,000 p s i No. | D.Fir D.Fir Parallam | D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL | 1650f 1.5E 2400f 2.0E PSL Stress p s i i Stress p s i 2575 3750 5000 | 2575 3750 5000 1 | 0.056 0.063 0.071 | 1.312 1.698 2.025 2 I 0.051 0. 069 0.074 | 1.437 1.555 1.936 3 I 0.065 0.059 0.069 | 1.135 1.820 2.064 4 I 0.055 0.052 0.073 | 1.33.6 2.057 1.968 5 I 0.047 0.058 0.071 | 1.577 1.847 2.008 6 1 0.054 0.054 0.070 | 1.366 2.013 2.041 7 | 0.047 0.051 0.070 • | 1.564 2.094 2.040 8 I 0.048 0.052 0.072 | 1.537 2.069 1.999 9 I 0.050 0.055 0.070 | 1.478 1.941 2. 060 10 | 0.047 0.051 0.067 | 1.566 2.104 2.129 11 1 0.047 0. 047 0.069 | 1.572 2.283 2.076 12 1 0.047 0.058 0.070 | 1.577 1.902 2.038 13 0.047 0.054 0.067 | 1.578 1.989 2.139 14 1 0.048 0. 052 0.068 | 1.537 2.078 2.103 15 0. 046 0.054 0.067 | 1.610 1.990 2.149 16 0.042 0.050 0.062 | 1.758 2.144 2.315 17 0.046 0.048 0.069 | 1.623 2.266 2.082 18 0.047 0. 061 0.069 | 1.577 1.749 2. 075 19 0.044 0.048 0.066 | 1.670 2.227 2.178 20 0.033 0. 052 0.064 | 2.234 2.102 2.245 21 0.044 0.048 0.062 | 1.691 2.250 2.310 22 0.039 0.048 0.065 | 1.897 2.241 2.213 23 0.046 0.044 0.062 | 1.610 2.445 2.309 24 0.057 0.047 0.064 | 1.308 2.286 2.239 25 | 0.040 0. 045 0.062 | 1.851 2.400 2.314 26 0.036 0.047 0.061 | 2.053 2.277 2. 347 27 0. 038 0.047 0.063 | 1.941 2.281 2.270 28 | 0.036 0.044 0.060 ' | 2.082 2.433 2.396 29 0.041 0.044 0.059 | 1.815 2.452 2.415 30 0.041 0.044 0.057 | 1.857 2.429 2.516 31 0.033 0.048 0.060 | 2.238 2.284 2.388 32 0.037 0. 044 0.055 | 2.016 2.471 2.606 33 0.034 0.042 0.055 | 2.177 2.586 2.606 34 0. 037 0. 037 0.057 | 2.026 2.930 2. 522 S t a t i s t i c a l Data: Mean 0. 045 0.051 0.065 | 1.694 2.167 2. 209 CV% 16.5 13.1 8.1 | 16.6 12.8 8.4 n 34 34 34 | 34 34 34 Range | Low 0.033 0.037 0.055 | 1.135 1.555 1.936 High i 0. 065 0.069 0.074 | 2. 238 2.930 2.606 175 Appendix I I I DEFLECTION AND FRACTIONAL CREEP RESULTS TABLE I I I - l 176 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 1 Creep Data at t = D e f l e c t i o n ( d t ) , i n . Beam No. 1 min. D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL 2060 Stress p s i 3000 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 4000 | 2060 3000 4000 0.060 | 1.00 1.00 1.00 0.058 | 1.00 1.00 1.00 0.063 | 1.00 1.00 1.00 0.056 | 1.00 1.00 1.00 0.067 | 1.00 1.00 1.00 0.056 | 1.00 1.00 1.00 0.059 | 1.00 1.00 1.00 0.055 | 1.00 1.00 1.00 0.053 | 1.00 1.00 1.00 0.056 | 1.00 1.00 1.00 0.054 | 1.00 1.00 1.00 0.053 | 1.00 1.00 1.00 0.054 | 1.00 1.00 1.00 0.053 | 1.00 1.00 1.00 0.055 | 1.00 1.00 1.00 0.057 | 1.00 1.00 1.00 0.057 | 1.00 1.00 1.00 0.052 | 1.00 1.00 1.00 0.052 | 1.00 1.00 1. 00 0.054 | 1.00 1.00 1.00 0.052 | 1.00 1.00 1.00 0.054 | 1.00 1.00 1.00 0.052 | 1. 00 1.00 1. 00 0.053 | 1.00 1.00 1. 00 0.051 | 1.00 1. 00 1.00 0.050 | 1.00 1.00 1.00 0.047 | 1.00 1.00 1.00 0.050 | 1.00 1.00 1.00 0.050 | 1.00 1.00 1.00 0.050 | 1.00 1. 00 1.00 0.046 | 1.00 1.00 1. 00 0.048 | 1.00 1.00 1. 00 0.047 | 1.00 1.00 1.00 0.048 | 1.00 1.00 1.00 0.054 | 1.00 1.00 1.00 8.5 | 0.0 0.0 0.0 34 | 34 34 34 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 26 27 28 29 30 31 32 33 34 0.041 0 . 050 0.044 0.046 0.041 0. 043 0.046 0.048 0. 040 0.039 0 . 038 0.037 0.038 0.034 0.035 0.032 0.035 0.035 0.036 038 034 030 035 0.034 0.030 034 029 033 032 0. 029 0.027 0.030 0. 027 0.025 0. 064 0.049 0.044 0. 047 0. 045 0.043 0. 045 0.052 0.050 0.043 0.041 0.047 0.044 0. 042 045 037 0.039 0.039 0. 039 038 036 0.038 0. 036 . 043 .038 . 037 . 037 .032 0 . 035 0. 033 0.035 0.035 0. 036 0.029 0. 0, 0 0 0 0 0 0 0 S t a t i s t i c a l Data; Mean CV% n Range Low High 0.036 17.4 34 0.025 n. o^o 0.041 16. 5 34 0.029 0.046 J L J l f c Z . 00 DIL 1, JL 00 HQ. 1.00 1 - 00 TABLE III-2 177 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 1 Beam No. Creep Data at t D e f l e c t i o n ( d t ) , i n . 28 hr. D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL Stress p s i | 2060 1 | 0.049 2 I 0.051 3 I 0. 047 4 I 0.049 5 I 0.041 6 | 0.043 7 | 0.050 8 I 0.055 9 I 0.041 10 | 0.042 11 1 0.039 12 | 0. 038 13 | 0.039 14 | 0.036 15 | 0.037 16 | 0. 036 17 | 0.038 18 | 0.035 19 | 0.038 20 | 0.040 21 | 0.034 22 | 0.031 23 | 0.036 24 | 0.034 25 | 0.031 26 | 0.036 27 . | 0.029 28 | 0.035 29 | 0.034 30 | 0.034 31 | 0. 028 32 | 0.033 33 | 0.030 34 | 0.026 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL Stress p s i 3000 4000 | 2060 3000 4000 0.082 0.064 | 1.20 1.28 1.07 0.051 0.062 | 1.02 1.04 1.07 0. 045 0.069 | 1.07 1.02 1.10 0.048 0.062 | 1.07 1.02 1.11 0.048 0.074 | 1.00 1.07 1.10 0.045 0.061 | 1.00 1.05 1.09 0. 048 0.063 | 1.09 1.07 1.07 0. 054 0.059 | 1.15 1.04 1.07 0. 052 0.057 | 1.03 1.04 1.08 0.045 0.061 | 1.08 1.05 1.09 0.043 0.060 | 1.03 1.05 1.11 0. 049 0.056 1 1.03 1.04 1.06 0.045 0.058 | 1.03 1.02 1.07 0.044 0.058 | 1.06 1.05 1.09 0.047 0.061 | 1.06 1.04 1.11 0.044 0.061 | 1.12 1.19 1.07 0.042 0.058 | 1.09 1.08 1.02 0.041 0.057 | 1.00 1.05 1.10 0.042 0.055 | 1.06 1.08 1.06 0.039 0.057 | 1.05 1.03 1.06 0.042 0.055 | 1.00 1.17 1.06 0.039 0.058 | 1.03 1.03 1.07 0. 038 0.055 | 1.03 1.06 1.06 0.045 0.054 | 1.00 1.05 1.02 0. 040 0.052 | 1.03 1.05 1.02 0.039 0.054 | 1.06 1.05 1.08 0.039 0.050 | 1.00 1.05 1.06 0.036 0.051 | 1.06 1.13 1.02 0. 037 0.055 | 1.06 1.06 1.10 0.036 0.053 | 1.17 1.09 1.06 0.035 0.049 | 1.04 1.00 1.07 0.037 0.050 | 1.10 1.06 1.04 0.038 0.052 | 1.11 1.06 1.11 0.031 0.050 | 1.04 1.07 1.04 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.038 18. 3 34 0.026 0.055 0. 044 19.6 34 0.031 0.082 0.057 9.6 34 0.049 0.074 1.06 4.6 34 1. 1. 00 20 1.06 5.0 34 1.00 1.28 1.07 2.5 34 1.02 1.11 TABLE i n - 3 17 8 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 1 Beam No. Creep Data at t = 100 hr D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL I 2060 1 | 0.051 2 I 0.053 3 | 0.048 4 I 0.052 5 I 0.043 6 I 0.045 7 1 0.052 8 I 0.058 9 I 0.042 10 | 0.043 11 1 0.040 12 | 0.038 13 | 0.041 14 | 0.036 15 | 0. 040 16 | 0. 037 17 | 0.039 18 | 0.037 19 | 0.039 20 | 0.042 21 | 0. 036 22 | 0.031 23 | 0.037 24 | 0.034 25 | 0.031 26 | 0.037 27 | 0.029 28 | 0.035 29 | 0.035 30 | 0.034 31 I 0. 028 32 | 0.033 33 | 0.031 34 | 0. 027 Stress p s i 3000 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 4000 | 2060 3000 0.067 | 1.24 1.45 0.065 | 1.06 1.08 0.072 | 1.09 1.11 0.064 | 1.13 1.06 0.079 | 1.05 1.16 0.063 | 1.05 1.09 0.064 | 1.13 1.11 0.060 | 1.21 1.10 0.058 | 1.05 1.06 0.062 | 1.10 1.09 0.063 | 1.05 1.07 0.058 | 1.03 1.09 0.060 | 1.08 1.07 0.059 | 1.06 1.10 0.064 | 1.14 1.11 0.063 | 1.16 1.24 0.059 | 1.11 1.10 0.058 | 1.06 1.13 0.058 | 1.08 1.10 0.059 | 1.11 1.05 0.057 | 1.06 1.17 0.060 | 1.03 1.05 0.059 | 1.06 1.08 0.055 | 1.00 1.07 0.053 | 1.03 1. 05 0.055 | 1.09 1.05 0.050 | 1.00 1.05 0.052 | 1.06 1.13 0.057 | 1.09 1.06 0.054 | 1.17 1.12 0.050 | 1.04 1.00 0.052 | 1.10 1.11 0.053 | 1.15 1.11 0.051 | 1.08 1.10 4000 0.093 0.053 0.049 0.050 0.052 0.047 0.050 0.057 0.053 0.047 0.044 0.051 0.047 0.046 0.050 046 043 044 043 040 042 040 0.039 0.046 0.040 0.039 0.039 0. 036 0.037 0.037 0.035 0.039 0.040 0.032 1.12 1.12 1.14 1.14 1, 1. 1. 1, 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 18 13 08 09 09 11 17 09 11 11 16 11 04 12 12 09 10 11 13 04 04 10 06 04 14 08 09 08 13 06 S t a t i s t i c a l Data: Mean CV% n Range Low Hiorh 0.039 19.4 34 0.027 0. 058 0.045 22.7 34 0.032 0.093 0.059 10.5 34 0.050 0.079 1.09 5.1 34 00 24 1.10 6.8 34 00 45 1.10 3.3 34 04 18 TABLE I I I-4 179 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 1 Beam No. Creep Data at t = 288 hr, D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir 1650f 1.5E 2400f 2. OE i 2060 1 | 0.054 2 I 0.055 3 I 0.053 4 I 0.056 5 I 0.044 6 I 0.049 7 | 0.054 8 I 0.064 9 I 0.043 10 | 0.049 11 1 0.043 12 | 0.039 13 | 0.043 14 | 0.038 15 | 0.042 16 | 0.040 17 | 0. 040 18 | 0.037 19 | 0.042 20 | 0.045 21 | 0.038 22 | 0.032 23 | 0. 040 24 | 0.036 25 | 0.031 26 | 0. 038 27 | 0.030 28 | 0.036 29 | 0.035 30 | 0.038 31 | 0.028 32 [ 0.036 33 | 0.032 34 | 0.030 Stress p s i 3000 F r a c t i o n a l Creep, d t / d l Parallam D.Fir D.Fir PSL 1650f 1.5E 2400f 2.0E 1 Stress p s i 4000 2060 3000 0.069 1.32 1.70 0.068 1.10 1.14 0.076 1.20 1.14 0.067 1.22 1.09 0.086 1.07 1.24 0.068 1.14 1.14 0.066 1.17 1.18 0.062 1.33 1.13 0.061 1.07 1.12 0.068 1.26 1.26 0.066 1.13 1.17 0.060 1.05 1.15 0.064 1.13 1.11 0.062 1.12 1.19 0.068 1.20 1.16 0.067 1.25 1.30 0.061 1.14 1.15 0.062 1.06 1.18 0. 060 1.17 1.21 0.062 1.18 1.11 0.059 1.12 1.25 0.063 1. 07 1.08 0.062 1.14 1.14 0.056 1.06 1.12 0.055 1.03 1.08 • 0.059 1.12 1.11 0.050 1.03 1.14 0.054 1.09 1.19 0.062 1.09 1.14 0.056 1.31 1.21 0.051 1.04 1.14 0.054 1.20 1.20 0.057 1.19 1.14 0.053 1.20 1.17 Parallam PSL 4000 0.109 0.056 0.050 0.051 0.056 0.049 0.053 0.059 0.056 0.054 0.048 0.054 0.049 0.050 0.052 0.048 0.045 0.046 .047 .042 .045 .041 .041 0.048 0.041 0.041 0.042 0. 038 0.040 0.040 0.040 0. 042 0.041 0.034 0. 0, 0. 0, 0, 1. 1. 1, 1. 1. 1. 1. 15 17 21 20 28 21 12 1.13 1.15 1, 1, 1, 1, 1, 1. 1, 1, 1, 1, 1, 21 22 13 19 17 24 18 07 19 15 15 1.13 1.17 1.19 1.06 1.08 1.18 1, 1, 1, 1, 1, 1, 1, 1, 06 08 24 12 11 13 21 10 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.041 20.7 34 0.028 0.064 0.048 25.5 34 0.034 0.109 0.062 11.5 34 0.050 0.086 1.15 7.2 34 1.03 1.33 1.18 9.1 34 1, 1, 08 70 1.16 4.8 34 1. 1, 06 28 TABLE I H-5 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA 180 85-12-30 Stress Level 1 Beam No. Creep Data at t D e f l e c t i o n ( d t ) , i n . 529 hr. D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL 1 Stress p s i j j 2060 3000 4000 | 2060 1 | 0.058 0.000 0.073 | 1.41 2 I 0.063 0.063 0.071 | 1.26 3 I 0.063 0.053 0.082 | 1.43 4 | 0.062 0.056 0.068 | 1.35 5 I 0.046 0.062 0.093 | 1.12 6 1 0.052 0.054 0.073 | 1.21 7 | 0.060 0.059 0.073 | 1.30 8 | 0.073 0.070 0.066 | 1.52 9 1 0.047 0.060 0.063 | 1.17 10 | 0.052 0.058 0.071 | 1.33 11 1 0.046 0.053 0.068 | 1.21 12 | 0.043 0.057 0.063 | 1.16 13 | 0.050 0.054 0.070 | 1.32 14 | 0.041 0.054 0.065 | 1.21 15 | 0.046 0.053 0.070 | 1.31 16 | 0.042 0.050 0.072 | 1.31 17 | 0.042 0.050 0.063 | 1.20 18 | 0.042 0.049 0.065 | 1.20 19 | 0.046 0.052 0.063 | 1.28 20 | 0.049 0.045 0.065 | 1.29 21 | 0.042 0.051 0.065 | 1.24 22 | 0.034 0.046 0.066 | 1.13 23 | 0.045 0.041 0.068 | 1.29 24 | 0.041 0.052 0.059 | 1. 21 25 | 0.036 0.044 0.057 | 1.20 26 | 0.039 0.043 0.062 | 1.15 27 | 0.033 0.045 0.052 | 1.14 28 | 0.039 0.040 0.056 | 1.18 29 | 0.039 0.041 0.066 | 1.22 30 | 0.038 0.040 0.058 | 1.31 31 I 0.029 0.044 0.053 | 1.07 32 | 0.037 0.043 0.056 | 1.23 33 | 0.035 0.044 0.059 | 1.30 34 | 0.033= 0.037 0.056 | 1.32 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 3000 4000 0. 1. 1, 1. 1. 1, 1, 1, 1, 1, 1, 1, 1. 1, 1. 1. 1. 1, 1. 1. 1. 1. 1, 1, 1, 1, 1. 1. 1, 1, 1, 1, 1. 1, 00 29 20 19 38 26 31 35 20 35 29 21 23 29 18 35 28 26 33 18 42 21 14 21 16 16 22 25 17 21 26 23 22 28 1.22 1.22 1.30 1.21 1.39 1.30 1.24 1.20 1.19 1.27 1.26 1.19 1.30 1.23 1. 1. 1, 1, 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 27 26 11 25 21 20 25 22 31 11 12 24 11 12 32 16 15 17 26 17 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.045 22.4 34 0.029 0.073 0.050 15.4 33 0.037 0.070 0.066 12.5 34 0.052 0.093 1.25 7.6 34 1. 07 1.52 1.25 5.5 33 1.14 1.42 1.22 5.6 34 1.11 1.39 TABLE.. 1 1 1- 6 181 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 1 Beam No. Creep Data at t = 1200 hr, D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL 1 Stress p s i j j 2060 3000 4000 | 2060 1 | 0.060 0.000 0.075 | 1.46 2 I 0.063 0.063 0.073 | 1.26 3 I 0.063 0.055 0.086 | 1.43 4 i 0.065 0.057 0.071 | 1.41 5 I 0.048 0.064 0.101 | 1.17 6 | 0.056 0.055 0.075 | 1.30 7 | 0.061 0.060 0.073 | 1.33 8 I 0.078 0.070 0.067 | 1.63 9 1 0.048 0.061 0.065 | 1.20 10 | 0.054 0.058 0.072 | 1.38 11 1 0.046 0.053 0.071 | 1.21 12 | 0.045 0.059 0.063 | 1.22 13 | 0.050 0.054 0.070 | 1.32 14 | 0.041 0.055 0.066 | 1.21 15 | 0.047 0.055 0.073 | 1.34 16 | 0.042 0.050 0.072 | 1.31 17 | 0.046 0.050 0.065 | 1.31 18 | 0.042 0.051 0.067 | 1.20 19 | 0.047 0.053 0.066 | 1.31 20 | 0.050 0.046 0.066 | 1.32 21 | 0.043 0.052 0.065 | 1.26 22 | 0.034 0.046 0.068 | 1.13 23 | 0.046 0.045 0.069 | 1.31 24 | 0.040 0.053 0.059 | 1.18 25 | 0.036 0.044 0.058 | 1.20 26 | 0.039 0.044 0.064 | 1.15 27 | 0.033 0. 045 0.054 | 1.14 28 | 0.039 0.041 0.057 | 1.18 29 | 0.037 0.041 0.067 | 1.16 30 | 0.040 0.043 0.060 | 1.38 31 | 0.030 0.042 0.054 | 1.11 32 | 0.037 0. 045 0.058 | 1.23 33 | 0.036 0.046 0.061 | 1.33 34 | 0.033 0.038 0.056 | 1.32 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 3000 4000 0.00 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 29 25 21 42 28 33 35 22 35 29 26 23 31 1.22 1.35 1.28 1.31 1.36 1.21 1.44 1.21 1.25 1.23 1. 1. 1. 1. 1. 1. 1. 1. 16 19 22 28 17 30 20 29 1.28 1.31 1.25 1.26 1.37 1.27 1. 1, 1, 1. 51 34 24 22 1.23 1, 1. 1, 1, 1, 1. 1. 1. 1, 1, 1. 1. 1. 1. 29 31 19 30 25 33 26 14 29 27 22 25 26 33 1.11 1.14 1.28 1.15 1. 1. 1. 1. 1. 1. 1. 14 34 20 17 21 30 17 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.046 23.5 34 0.030 0.078 0.051 14.9 33 0.038 0.070 0.067 13.6 34 0. 054 0.101 1.28 8.7 34 1.11 1.63 1.27 5.3 33 1.16 1.44 1.25 6.4 34 1.11 1.51 TABLE l i i _ 7 182 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 1 Beam No. Creep Data at t = 2325 hr. Deflection (dt), in. D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL 1 Stress psi j j 2060 3000 4000 | 2060 1 | 0.063 0.000 0.078 | 1.54 2 I 0.065 0.064 0.074 | 1.30 3 | 0.064 0.057 0.090 | 1.45 4 I 0.067 0.059 0.074 | 1.46 5 I 0.050 0.067 0.110 | 1.22 6 1 0.059 0.058 0.079 | 1.37 7 | 0.063 0.062 0.076 | 1.37 8 i 0.087 0.074 0.069 | 1.81 9 | 0.049 0.063 0.067 | 1.22 10 | 0.057 0.059 0.073 | 1.46 11 1 0.050 0.057 0.072 | 1.32 12 | 0.045 0.062 0.066 | 1.22 13 | 0.052 0.058 0.076 | 1.37 14 | 0.042 0.058 0.068 | 1.24 15 | 0.050 0.057 0.078 | 1.43 16 | 0.043 0.050 0.077 | 1.34 17 | 0.047 0.051 0.071 | 1.34 18 | 0.043 0.053 0.069 | 1.23 19 | 0.049 0.055 0.067 | 1.36 20 | 0.050 0.047 0.069 | 1.32 21 | 0.044 0.052 0.068 | 1.29 22 | - 0.035 0.047 0.069 | 1.17 23 | 0.048 0.046 0.072 | 1.37 24 | 0. 042 0. 055 0.061 | 1.24 25 | 0.038 0.046 0.059 | 1.27 26 | 0.040 0.045 0.065 | 1.18 27 | 0.033 0.047 0.056 | 1.14 28 | 0.039 0.043 0.058 | 1.18 29 | 0.039 0.042 0.070 | 1.22 30 | 0.040 0.045 0.062 | 1.38 31 1 0.033 0.044 0.056 | 1.22 32 | 0.039 0.047 0.059 | 1.30 33 | 0.037 0.047 0.063 | 1.37 34 | 0.034 0.038 0.057 | 1.36 Fractional Creep, dt/dl D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL Stress psi 3000 4000 0.00 1.31 1. 1. 1. 1. 1, 1. 1. 1. 1. 30 26 49 35 38 42 26 37 39 1.32 1.32 1.38 1.27 1.35 1.31 1.36 1.41 1.24 1.44 1.24 1.28 1.28 1.21 1.22 1.27 1.34 1.20 1.36 1.26 1.34 1.31 1.31 1. 1. 1, 1, 1. 1, 1, 1, 1, 1. 1. 1, 1, 1, 1, 1. 1, 1, 1. 1. 1, 1, 1. 1, 1. 1, 1, 1, 1. 1, 1, 1. 1, 1, 30 28 43 32 64 41 29 25 26 30 33 25 41 28 42 35 25 33 29 28 31 28 38 15 16 30 19 16 40 24 22 23 34 19 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.048 24. 7 34 0.033 0.087 0.053 15.5 33 0.038 0.074 0.070 14.9 34 0.056 0.110 1.32 9.8 34 1.14 1.81 1.32 5.3 33 1.20 1.49 1.30 7.4 34 1. 1. 15 64 TABLE i n _ 8 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 1 Creep Data at t = 3662 hr D e f l e c t i o n ( d t ) , i n . Beam No. D.Fir 1 2060 1 | 0.065 2 I 0.068 3 1 0.071 4 I 0.070 5 I 0.051 6 1 0.061 7 I 0.066 8 I 0.092 9 1 0.050 10 | 0.057 11 1 0.051 12 | 0.046 13 | 0.052 14 | 0.044 15 | 0.052 16 | 0.044 17 | 0.047 18 | 0.044 19 | 0.050 20 | 0.052 21 | 0.047 22 | 0.035 23 | 0.050 24 | 0.040 25 | 0.039 26 | 0.042 27 [ 0.035 28 | 0.043 29 | 0.040 30 | 0.042 31 I 0.033 32 | 0.041 33 | 0.039 34 | 0.037 F r a c t i o n a l Creep, d t / d l D.Fir Parallam D.Fir D.Fir 2400f 2.0E PSL 1650f 1.5E 2400f 2.0E Stress p s i Stress p s i 3000 4000 | 2060 3000 0.000 0.080 | 1.59 0.00 0.067 0.076 | 1.36 1.37 0.057 0.094 1.61 1.30 0.062 0.077 | 1.52 1.32 0.068 0.000 | 1.24 1.51 0.060 0.082 | 1.42 1.40 0.065 0.080 | 1.43 1.44 0.077 0.072 | 1.92 1.48 0.065 0.068 | 1.25 1.30 0.062 0.076 | 1.46 1.44 0.059 0.076 | 1.34 1.44 0.062 0.068 | 1.24 1.32 0.058 0.076 | 1.37 1.32 0.062 0.071 | 1.29 1.48 0.058 0.081 | 1.49 1.29 0.053 0.081 | 1.37 1.43 0.052 0.071 | 1.34 1.33 0.054 0.072 | 1.26 1.38 0.056 0.069 | 1.39 1.44 0.049 0.070 | 1.37 1.29 0.054 0.070 | 1.38 1.50 0.048 0.072 | 1.17 1.26 0.047 0.075 1.43 1.31 0.057 0.063 | 1.18 1.33 0.046 0.061 | 1.30 1.21 0.046 0.068 1.24 1.24 0.048 0.057 | 1.21 1.30 0.043 0.060 | 1.30 1.34 0.042 0.072 1.25 1.20 0.045 0.063 1.45 1. 36 0.047 0.057 | 1.22 1. 34 0.048 0.063 1.37 1.37 0.049 0.066 | 1.44 1.36 0.039 0.060 j 1.48 1.34 Parallam PSL 4000 1.33 1.31 1.49 1.38 0.00 1. 1, 1. 1. 1. 1, 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 46 36 31 28 36 41 28 41 34 47 42 25 38 33 30 35 33 44 19 1.20 1.36 1. 1. 1, 1, 1, 1, 1, 1, 21 20 44 26 24 31 40 25 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.050 25.5 34 0.033 0.092 0.055 16.0 33 0.039 0.077 0.071 11.5 33 0.057 0.094 1.37 10.8 34 1.17 1.92 1.36 5.9 33 1.20 1.51 1.33 6.3 33 1.19 1.49 TABLE H l - 9 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA 184 85-12-30 Stress Level 1 Creep Data at t = 5568 hr D e f l e c t i o n ( d t ) , i n . Beam No. D.Fir D.Fir 1650f 1.5E 2400f 2.0E 1 2060 1 | 0.066 2 I 0.069 3 | 0.072 4 I 0.071 5 I 0.053 6 I 0.061 7 | 0.067 8 I 0.095 9 I 0.050 10 | 0. 060 11 1 0.052 12 | 0. 046 13 | 0.052 14 | 0.044 15 | 0.052 16 | 0.045 l " 7 1 0.048 18 | 0.045 19 | 0.051 20 | 0.052 21 | 0.048 22 | 0.036 23 | 0. 052 24 | 0.044 25 | 0.040 26 | 0. 042 27 | 0.035 28 | 0.044 29 | 0.040 30 | 0.043 31 | 0.033 32 | 0.042 33 | 0.039 34 | 0.037 Stress p s i 3000 F r a c t i o n a l Creep, d t / d l Parallam D.Fir D.Fir Parallam PSL 1650f 1.5E 2400f 2.0E PSL 1 Stress p s i 4000 | 2060 3000 4000 0.081 | 1.61 0.00 1.35 0.077 1.38 1.39 1.33 0.096 1.64 1.30 1.52 0.077 1.54 1.36 1.38 0.000 | 1.29 1.51 0.00 0.083 1.42 1.40 1.48 0.082 1.46 1.47 1.39 0.072 1.98 1.50 1.31 0.068 1.25 1.34 1.28 0.076 1.54 1.42 1.36 0.076 1.37 1.44 1.41 0.069 1.24 1.36 1.30 0.076 1.37 1.36 1.41 0.072 1.29 1.52 1.36 0.081 1.49 1.33 1.47 0.081 1.41 1.46 1.42 0.072 1.37 1.38 1.26 0.073 1.29 1.38 1.40 0.070 1.42 1.44 1.35 0.072 1.37 1.32 1.33 0.071 1.41 1.56 1.37 0.073 1.20 1.29 1.35 0.076 1.49 1.33 1.46 0.064 1.29 1.37 1.21 0.062 1.33 1.24 1.22 0.069 1.24 1.30 1.38 0.059 1.21 1.30 1.26 0.061 1.33 1.37 1.22 0.073 1.25 1.20 1.46 0.064 1.48 1.36 1.28 0.058 1.22 1.40 1.26 0.063 1.40 1.43 1.31 0.067 1.44 1.36 1.43 0.060 1.48 1.38 1.25 0.000 0.068 0.057 0.064 0.068 0.060 0.066 0.078 0.067 0.061 0.059 0.064 0.060 0.064 0.060 0.054 0.054 0.054 0.056 0.050 .056 .049 ,048 .059 .047 .048 0.048 0.044 0.042 0.045 0.049 0.050 0.049 0.040 0, 0, 0. 0, 0, 0, S t a t i s i c a l Data: Mean CV% n Range Low High 0.051 25.8 34 0.033 0.095 0.056 15.9 33 0.040 0.078 0.072 11.4 33 0. 058 0.096 I. 40 I I . 0 34 1.20 1.98 1.38 5.7 33 1.20 1.56 1.35 6.1 33 1.21 1.52 185 TABLE 1 1 1 - 1 0 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 1 Creep Data at t D e f l e c t i o n ( d t ) , i n . Beam No. 7416 hr. D.Fir D.Fir 1650f 1.5E 2400f 2.OE I 2060 1 | 0.067 2 I 0.069 3 1 0.073 4 I 0.073 5 I 0.053 6 1 0.061 7 | 0.070 8 I 0.105 9 1 0.051 10 | 0.061 11 1 0.052 12 | 0.047 13 | 0.054 14 | 0.044 15 | 0.053 16 | 0.045 17 | 0.048 18 | 0.046 19 | 0.053 20 | 0.052 21 | 0.048 22 | 0.037 23 | 0.053 24 | 0.047 25 | 0.041 26 | 0.043 27 | 0.037 28 | 0.046 29 | 0.040 30 | 0.044 31 | 0.033 32 | 0.042 33 | 0.040 34 | 0.039 Stress p s i 3000 F r a c t i o n a l Creep, d t / d l Parallam D.Fir D.Fir Parallam PSL 1650f 1.5E 2400f 2.0E PSL 1 Stress p s i 4000 | 2060 3000 4000 0.081 | 1.63 0.00 1.35 0.078 1.38 1.43 1.34 0.096 1.66 1.32 1.52 0.077 1.59 1.36 1.38 0.000 1. 29 1.53 0.00 0.084 1.42 1.40 1.50 0.082 1.52 1.47 1.39 0.073 2.19 1.50 1.33 0.070 1. 27 1.34 1.32 0.077 1. 56 1.42 1.38 0.077 1.37 1.56 1.43 0.070 1.27 1.40 1.32 0.078 1.42 1.39 1.44 0.074 | 1.29 1.52 1.40 0.083 1.51 1.36 1.51 0.082 1.41 1.46 1.44 0.073 1.37 1.44 1.28 0.075 1.31 1.44 1.44 0.071 1.47 1.44 1.37 0.073 1.37 1.34 1.35 0.072 1.41 1.61 1.38 0.074 1.23 1.34 1.37 0. 078 1.51 1.33 1.50 0.065 1.38 1.42 1.23 0.062 1.37 1.29 1.22 0.071 1.26 1.30 1.42 0. 060 1.28 1.32 1.28 0.062 1.39 1.37 1.24 0.074 1.25 1.23 1.48 0.065 1.52 1.36 1.30 0.058 1.22 1.46 1.26 0.064 1.40 1.43 1.33 0.069 1.48 1.42 1.47 0.061 1.56 1.41 1.27 0.000 0.070 0.058 0.064 0.069 0.060 0.066 0.078 0.067 0.061 0.064 0.066 0.061 0.064 0.061 0.054 0.056 0.056 0.056 0.051 0.058 0.051 0.048 0.061 0.049 ,048 ,049 .044 ,043 ,045 ,051 0.050 0.051 0.041 0. 0, 0. 0, 0. 0. S t a t i s t i c a l Data: Mean CV% n Range Low High 0.052 27.2 34 0.033 0.105 0.057 15.6 33 0.041 0.078 0.073 11.2 33 0.058 0.096 1.43 12.5 34 1.22 2.19 1.41 5.8 33 1.23 1.61 1.37 6.3 33 1.22 1.52 TABLE I I I - l l CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA 186 85-12-30 Stress Level 1 Beam No. Creep Data at t =11210 hr D e f l e c t i o n ( d t ) , i n . D.Fir , 1 2060 1 | 0.068 2 I 0.072 3 I 0.075 4 I 0.075 5 I 0.053 6 I 0.064 7 I 0.073 8 I 0.116 9 I 0.052 10 | 0.062 11 1 0.053 12 | 0.049 13 | 0.054 14 | 0.045 15 | 0.055 16 | 0.047 17 | 0.050 18 | 0.046 19 | 0.053 20 | 0.054 21 | 0.049 22 | 0.037 23 | 0.055 24 | 0.047 25 | 0.041 26 | 0.043 27 | 0.037 28 | 0.047 29 | 0.042 30 | 0. 046 31 I 0.035 32 | 0.043 33 | 0.041 34 | 0. 040 F r a c t i o n a l Creep, d t / d l D.Fir Parallam D.Fir D.Fir 2400f 2.0E PSL 1650f 1.5E 2400f 2.0E Stress p s i Stress p s i 3000 4000 | 2060 3000 0.000 0.083 1.66 0.00 0.071 0.079 1.44 1.45 0.060 0.100 1.70 1.36 0.065 0.079 1.63 1.38 0.071 0.000 1.29 1.58 0.062 0.086 1.49 1.44 0.068 0.084 1.59. 1.51 0.082 0.075 2.42 1.58 0.070 0.071 1.30 1.40 0.064 0.079 1.59 1.49 0.065 0.080 1.39 1.59 0.066 0.071 1.32 1.40 0.061 0.080 1.42 1.39 0.065 0.074 1.32 1.55 0.062 0.084 1.57 1.38 0.056 0.090 1.47 1.51 0.056 0.073 1.43 1.44 0.057 0.076 1.31 1.46 0.058 0.074 1.47 1.49 0.051 0.074 | 1.42 1.34 0.059 0.075 | 1.44 . 1.64 0.051 0.077 1.23 1. 34 0.050 0.081 | 1.57 1.39 0.063 0.067 | 1.38 1.47 0.049 0.063 1.37 1.29 0.049 0.072 | 1.26 1.32 0.051 0.060 | 1.28 1.38 0.045 0.062 | 1.42 1.41 0.043 0.077 | 1.31 1.23 0.048 0.067 | 1.59 1.45 0.051 0.060 j 1.30 1.46 0.053 0.065 | 1.43 1.51 0.053 0.070 | 1.52 1.47 0. 042 0.062 | 1.60 1.45 Parallam PSL 4000 1, 1, 1. 1. 0, 1. 1. 1. 1, 1, 1. 1, 1. 38 36 59 41 00 54 42 36 34 41 48 34 48 1.40 1.53 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 58 28 46 42 37 44 43 56 26 24 44 28 24 54 34 30 35 49 29 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.054 29.2 34 0.035 0.116 0.058 15.8 33 0. 042 0. 082 0. 075 12.0 33 0. 060 0.100 1.47 14.3 34 1.23 2.42 1.44 6.3 33 1, 1. 23 64 1.40 7.1 33 1, 1, 24 59 TABLE m - 1 2 - 187 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Beam Creep Data at t = 1 min Def l e c t i o n ( d t ) , i n . No. I D.Fir D.Fir Parallam D.Fir 1 1650f 1.5E 2400f 2.0E PSL 1650f 1.5E Stress p s i I 2325 3375 4500 | 2325 1 1 0.043 0.059 0. 069 1.00 2 0.049 0. 054 0.063 1.00 3 0.046 0.050 0.069 1.00 4 0.048 0.050 0.066 1.00 5 0.043 0.048 0.063 1.00 6 I 0.041 0.052 0.062 1.00 7 ! 0.048 0. 048 0.064 1.00 8 I 0.045 0. 050 0.059 1.00 9 I 0.047 0.047 0.061 1. 00 10 [ 0.043 0.041 0.061 1.00 11 I 0.047 0.051 0.062 1.00 12 I 0.038 0.049 0.060 1.00 13 1 0.041 0.048 0.059 1.00 14 1 0.037 0.044 0.059 1. 00 15 I 0.043 0.049 0.061 1.00 16 I 0.042 0.046 0.060 1. 00 17 1 0.039 0.046 0.060 1. 00 18 I 0.040 0. 045 0. 063 1.00 19 I 0.040 0. 046 0.053 1. 00 20 I 0.040 0.044 0.060 1.00 21 1 0.042 0. 043 0.059 1. 00 22 I 0.040 0.044 0.058 1.00 23 I 0.040 0.043 0. 058 1.00 24 1 0.041 0.038 0.057 1.00 25 0.038 0.033 0.058 1.00 26 I 0.036 0.041 0.054 1.00 27 1 0.033 0.043 0.057 1.00 28 1 0.034 0. 041 0.056 1.00 29 I 0.034 0.043 0.054 1.00 30 I 0.035 0. 040 0.056 1.00 31 i 0.032 0.043 0.051 1.00 32 I 0.031 0. 038 0.054 1.00 33 1 0.032 0.031 0.052 1.00 34 1 0.031 0.033 0.049 1.00 F r a c t i o n a l Creep, d t / d l D.Fir lOOf 2. 0E Parallam PSL Stress p s i 3375 4500 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1, 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1, 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 1.00 00 00 00 00 00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1. 1. 1, 1, 1, 1, 00 00 00 00 00 00 1.00 1, 1, 1, 1. 1, 1. 1, 1, 1. 1. 1. 1. 1. 1, 1. 1. 1. 1. 1, 1. 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.040 13.0 34 0.031 0.049 0. 045 13.4 34 0.031 0.059 0.059 7.9 34 0. 049 0. 069 1.00 0.0 34 00 00 1.00 0.0 34 1, 1. 00 00 1.00 0.0 34 1.00 1.00 TABLE —TTT=±3-CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Beam No. Creep Data at t = 28 hr De f l e c t i o n ( d t ) , i n . D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL 1 Stress p s i ! Stress p s i j 2325 3375 4500 | 2325 3375 1 1 0.046 0.067 0.071 | 1.07 1.14 2 I 0.053 0.056 0.068 | 1.08 1.04 3 I 0.048 0.052 0.075 | 1.04 1.04 4 I 0.049 0.053 0.072 | 1.02 1.06 5 I 0.044 0.048 0.068 | 1.02 1.00 6 | 0.041 0.055 0.068 | 1.00 1.06 7 1 0.048 0.050 0.068 1 1. 00 1. 04 8 I 0.048 0.053 0.063 | 1.07 1.06 9 1 0.050 0.048 0.067 | 1.06 1.02 10 | 0.044 0.045 0.064 | 1.02 1.10 11 1 0.049 0.057 0.066 | 1.04 1.12 12 | 0.041 0.052 0.063 | 1.08 1. 06 13 | 0.042 0.048 0.065 | 1.02 1.00 14 | 0.038 0.000 0.063 | 1.03 0. 00 15 | 0.000 0.058 0.069 | 0.00 1.18 16 | 0.044 0. 052 0.065 | 1.05 1.13 1.7 | 0.041 0.048 0.065 | 1.05 1. 04 18 | 0.042 0.048 0.067 | 1.05 1.07 19 | 0.041 0.049 0.063 | 1.03 1.07 20 | 0.043 0.045 0.063 | 1.07 1.02 21 | 0.044 0.045 0.062 | 1.05 1.05 22 | 0.041 0.048 0.063 | 1.03 1.09 23 | 0.043 0.043 0.062 | 1.07 1. 00 24 | 0.041 0.040 0.061 | 1.00 1. 05 25 | 0.041 0.034 0.063 | 1.08 1.03 26 | 0.040 0.043 0.057 | 1.11 1. 05 27 | 0.034 0.044 0.059 | 1.03 1.02 28 | 0.036 0.042 0.061 | 1. 06 1. 02 29 | 0.035 0.047 0.057 | 1.03 1.09 30 | 0.036 0.042 0.059 | 1.03 1.05 31 | 0.033 0.045 0.054 | 1. 03 1.05 32 | 0.031 0.039 0.058 | 1.00 1.03 33 | 0.033 0.035 0.058 | 1.03 1.13 34 | 0.032 0.034 0.053 | 1. 03 1.03 F r a c t i o n a l Creep, d t / d l D.Fir D . F i r Parallam 1650f 1.5E 2400f 2.OE PSL 4500 1. 1. 1. 1. 1. 1. 03 08 09 09 08 10 1.06 1.07 1.10 1.05 1.06 1.05 1.10 1.07 1.13 1. 1. 1. 1. 1. 1, 1, 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 08 08 06 19 05 05 09 07 07 09 06 04 09 06 05 06 07 12 08 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.042 13.5 33 0.031 0.053 0.047 15.0 33 0.034 0.067 0. 064 7.8 34 0.053 0.075 1.04 2.6 33 1.00 1.11 1.06 4.1 33 1. 1. 00 18 1.08 2.7 34 1.03 1.19 TABLE 1 1 1 - 1 4 189 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Beam No. Creep Data at t = 100 hr D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL 1 Stress p s i j 1 2325 3375 4500 | 2325 1 | 0.046 0.073 0.073 | 1.07 2 I 0.056 0.058 0.070 | 1.14 3 | 0.049 0.055 0.081 | 1.07 4 I 0.052 0.053 0.074 | 1.08 5 I 0.046 0.000 . 0.070 | 1.07 6 1 0. 045 0.057 0.070 | 1.10 7 | 0. 050 0. 000 0.069 | 1.04 8 I 0.050 0.053 0.065 | 1.11 9 1 0.052 0.050 0.069 | 1.11 10 | 0.046 0. 046 0.067 | 1.07 11 1 0.051 0.061 0.068 | 1.09 12 | 0.042 0.055 0.065 | 1.11 13 | 0.043 0.049 0.067 | 1.05 14 | 0.040 0.000 0.065 | 1.08 15 | 0.000 0.061 0.073 | 0.00 16 | 0.044 0.053 0.069 | 1.05 17 | 0.042 0.051 0.068 | 1.08 18 | 0.043 0.049 0.070 | 1.07 19 | 0.042 0.052 0.065 | 1.05 20 | 0.045 0.046 0.065 | 1.12 21 | 0.045 0.047 0.063 | 1.07 22 | 0.043 0.050 0.065 | 1.07 23 | 0. 044 0.046 0.064 | 1.10 24 | 0.043 0.043 0.063 | 1.05 25 | 0.042 0. 037 0.066 | 1.11 26 | 0.041 0.044 0.058 | 1.14 27 | 0.035 0.045 0.061 | 1.06 28 | 0.037 0.043 0.064 | 1.09 29 | 0.035 0. 049 0.059 | 1.03 30 | 0.037 0. 045 0.059 | 1.06 31 | 0.033 0. 047 0.057 | 1.03 32 | 0.032 0.040 0.060 | 1.03 33 | 0.033 0. 036 0.061 | 1.03 34 | 0. 032 0.035 0.053 | 1.03 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 3375 4500 1.24 1.07 1.10 1.06 0.00 1.10 0.00 1.06 1.06 1.12 1.20 1.12 1.02 0.00 1.24 1.15 1.11 1.09 1.13 1.05 1.09 1.14 1. 1. 1. 1. 1. 07 13 12 07 05 1.05 1.14 1.13 1. 1. 1. 1. 09 05 16 06 1. 1. 1. 1. 1, 1, 1. 1. 1, 1, 06 11 17 12 11 13 08 10 13 10 1.10 1.08 1.14 1.10 1.20 1.15 1.13 1.11 1.23 1.08 1.07 1.12 1. 1, 1, 1, 1, 1, 1, 1, 10 11 14 07 07 14 09 05 1.12 1.11 1.17 1.08 S t a t i s t i c a l Data; Mean CV% n Range Low High 0. 043 14.4 33 0.032 0.056 0.049 16.1 31 0.035 0.073 0.066 8.4 34 0.053 0.081 1.07 2.9 33 1.03 1.14 1.11 4.9 31 1.02 1.24 1.11 3.5 34 1.05 1.23 TABLE n i - 1 5 ]90 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Beam No. Creep Data at t De f l e c t i o n ( d t ) , i n . 288 hr. D.Fir D.Fir 1650f 1.5E 2400f 2.OE I 2325 1 | 0.047 2 I 0. 059 3 1 0.051 4 I 0.055 5 I 0.049 6 1 0.045 7 I 0.053 8 I 0. 053 9 1 0. 056 10 | 0.052 11 1 0.054 12 | 0.043 13 | 0.046 14 | 0.041 15 | 0.000 16 | 0.048 17 | 0.044 18 | 0.045 19 | 0.044 20 | 0. 048 21 | 0.048 22 | 0.045 23 | 0.046 24 | 0.044 25 | 0.045 26 | 0.044 27 | 0.037 28 | 0.040 29 | 0. 038 30 | 0.039 31 I 0.033 32 | 0.034 33 | 0.036 34 | 0.035 Stress p s i 3375 F r a c t i o n a l Creep, d t / d l Parallam D.Fir D.Fir Parallam PSL 1650f 1.5E 2400f 2.0E PSL 1 Stress p s i 4500 2325 3375 4500 0.075 1.09 1.32 1.09 0.074 1.20 1.13 1.17 0.085 1.11 1.16 1.23 0.078 1.15 1.12 1.18 0.073 1.14 0.00 1.16 0.073 1.10 1.13 1.18 0.072 1.10 0.00 1.13 0.067 1.18 1.08 1.14 0.074 1.19 1.15 1.21 0.071 1.21 1.20 1.16 0.070 1.15 1.27 1.13 0.068 1.13 1.16 1.13 0.072 1.12 1.13 1.22 0.069 | 1.11 0.00 1.17 0.076 0. 00 1.33 1.25 0.073 1.14 1.22 1.22 0.071 1.13 1.15 1.18 0.074 1.12 1.13 1.17 0.067 | 1.10 1.22 1.26 0.068 | 1.20 1.11 1.13 0.065 | 1.14 1.16 1.10 0.067 | 1.12 1.16 1.16 0.067 | 1.15 1.19 1.16 0.064 | 1.07 1.24 1.12 0.069 | 1.18 1.15 1.19 0.061 | 1.22 1.12 1.13 0.064 | 1.12 1.12 1.12 0.067 | 1.18 1.10 1.20 0.063 j 1.12 1.23 1.17 0.061 | 1.11 1.20 1.09 0.058 j 1.03 1.16 1.14 0.065 | 1.10 1.13 1.20 0.065 | 1.13 1.23 1.25 0.056 | 1.13 1.09 1.14 0.078 0.061 0.058 0.056 0.000 0.059 0.000 0.054 0. 054 0. 049 0.065 0.057 0. 054 0.000 0.065 0.056 0. 053 0.051 0. 056 0.049 0.050 051 051 047 038 0.046 0.048 045 053 048 050 043 038 036 0. 0. 0, 0. 0. 0. 0. S t a t i s t i c a l Data: Mean | 0. 045 0.052 0. 069 CV% | 14.6 16.3 8.6 n j 33 31 34 Range | Low j 0.033 0.036 0. 056 High | 0.059 0.078 0. 085 1.14 3.7 33 1.03 1.22 1.17 5.3 31 1.08 1.33 1.17 3.9 34 1.09 1.26 TABLE i n - 1 6 191 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Creep Data at t = 529 hr. Beam | Def l e c t i o n ( d t ) , i n . F r a c t i o n a l Creep, d t / d l No. | D.Fir D.Fir Parallam D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL 1650f 1.5E 2400f 2.0E PSL Stress p s i Stress p s i 2325 3375 4500 2325 3375 4500 1 | 0. 050 0. 087 0.079 1.16 1.47 1.14 2 I 0.065 0.069 0.079 1.33 1.28 1.25 3 I 0.059 0.061 0.090 1.28 1.22 1.30 4 I 0.060 0.061 0.082 1.25 1.22 1.24 5 I 0.053 0.000 0.077 1.23 0.00 1.22 6 I 0.050 0.063 0.077 1.22 1.21 1.24 7 I 0.058 0.000 0.075 1.21 0.00 1.17 8 I 0.059 0. 060 0.069 1.31 1.20 1.17 9 I 0.062 0.057 0.078 1.32 1.21 1.28 10 | 0.057 0.052 0.077 1.33 1.27 1.26 11 I 0.064 0.071 0.073 1.36 1.39 1.18 12 | 0.045 0.061 0.071 1.18 1.24 1.18 13 | 0.051 0.059 0.076 1.24 1.23 1.29 14 | 0.045 0.000 0.071 1.22 0.00 1.20 15 | 0.000 0.069 0.080 0.00 1.41 1.31 16 | 0.052 0.060 0.079 1.24 1.30 1.32 17 0.047 0.058 0.074 1.21 1.26 1.23 18 0.050 0. 055 0.081 1.25 1.22 1.29 19 | 0.048 0.060 0.071 1.20 1.30 1.34 20 j 0.053 0. 054 0.071 1.32 1.23 1.18 21 I 0.056 0.055 0.068 1.33 1.28 1.15 22 0.047 0.058 0.070 1.17 1.32 1.21 23 0.051 0.058 0.070 1.27 1.35 1.21 24 | 0.049 0.053 0.067 1.20 1.39 1.18 25 | 0.050 0.038 0.075 1.32 1.15 1.29 26 | 0. 045 0.050 0.063 | 1.25 1.22 1.17 27 | 0.041 0.053 0.066 | 1.24 1.23 1.16 28 | 0.047 0.050 0.071 | 1.38 1.22 1.27 29 | 0.044 0.057 0.068 1.29 1.33 1.26 30 I 0. 047 0.052 0.063 1.34 1.30 1.13 31 0.036 0.053 0.061 1.13 1.23 1.20 32 | 0. 036 0.044 0.069 1.16 1.16 1.28 33 | 0. 037 0.039 0.069 1.16 1.26 1.33 34 | 0.036 0.037 0.057 I 1.16 1.12 1.16 S t a t i s t i c a l Data: Mean 0.050 0.057 0.073 1.25 1.27 1.23 CV% 15.8 17.6 9.3 5.5 6.2 4.9 n 33 31 34 33 31 34 Range Low 0.036 0.037 0.057 1.13 1.12 1.13 High 0.065 0.087 0.090 1.38 1.47 1.34 TABLE 111-17 19:2 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Creep Data at t = 1200 hr Beam j D e f l e c t i o n ( d t ) . i n . j F r a c t i o n a l Creep, d t / d l No. | D.Fir D.Fir Parallam | D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL | 1650f 1.5E 2400f 2.0E PSL Stress p s i 1 Stress p s i 2325 3375 4500 | 2325 3375 4500 1 | 0. 052 0.000 0.080 | 1. 21 0.00 1.16 2 0.067 0.069 0.080 | 1.37 1.28 1.27 3 | 0.058 0.063 0.094 | 1.26 1.26 1.36 4 I 0.062 0.063 0.083 | 1.29 1.26 1.26 5 I 0.053 0.000 0.078 | 1.23 0.00 1.24 6 1 0.050 0.065 0.079 | 1.22 1.25 1.27 7 j 0.058 0.000 0.077 | 1.21 0.00 1.20 8 I 0. 061 0.060 0.071 | 1.36 1.20 1.20 9 1 0.064 0.057 0.081 | 1.36 1.21 1.33 10 | 0.058 0.053 0.080 | 1.35 1.29 1.31 11 1 0. 064 0.076 0.075 | 1.36 1.49 1.21 12 | 0. 046 0.061 0.074 | 1.21 1.24 1.23 13 j 0.050 0.059 0.078 | 1.22 1.23 1.32 14 I 0. 046 0.000 0.073 | 1.24 0.00 1.24 15 | 0. 000 0.070 0.081 | 0.00 1.43 1.33 16 0.052 0.060 0.081 | 1.24 1.30 1.35 17 | 0.047 0.058 0.076 | 1.21 1.26 1.27 18 0.051 0.056 0.082 | 1.27 1.24 1.30 19 0.048 0.064 0.071 | 1.20 1.39 1.34 20 | 0.054 0.054 0.072 | 1.35 1.23 1.20 21 I 0.056 0.056 0.070 | 1.33 1.30 1.19 22 | 0.049 0.058 0.073 | 1.23 1.32 1.26 23 | 0.051 0.056 0.072 | 1.27 1.30 1.24 24 | 0.051 0.053 0.069 | 1.24 1.39 1.21 25 | 0.050 0.041 0.076 | 1. 32 1.24 1.31 26 | 0.047 0.051 0.064 | 1.31 1.24 1.19 27 | 0.041 0.053 0.068 | 1.24 1.23 1.19 28 | 0.049 0.050 0.073 | 1.44 1.22 1.30 29 | 0.042 0.060 0.068 | 1. 24 1.40 1.26 30 | 0.044 0.053 0.063 | 1.26 1.33 1.13 31 I 0.036 0.054 0.063 | 1.13 1.26 1.24 32 | 0.037 0.044 0.071 | 1.19 1.16 1.31 33 | 0.037 0.042 0.070 | 1.16 1.35 1.35 34 | 0.037 0.039 0.058 | 1.19 1.18 1.18 S t a t i s t i c a l Data: Mean | 0.051 0.057 0.074 | 1.26 1.28 1.26 CV% | 16. 2 14.8 9.5 | 5.6 6.0 4.9 n 33 30 34 | 33 30 34 Range Low 0. 036 0.039 0.058 | 1.13 1.16 1.13 High 0. 067 0.076 0.094 | 1.44 1.49 1.36 TABLE 111-18 19.3 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Beam No. Creep Data at t D e f l e c t i o n ( d t ) , i n . 2325 hr. D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 2325 3375 4500 | 2325 3375 0.053 0.000 0.083 | 1.23 0.00 0.070 0.072 0.084 | 1.43 1.33 0.061 0.064 0.099 | 1.33 1.28 0.064 0.067 0.086 | 1. 33 1.34 0.056 0.000 0.082 | 1.30 0.00 0.051 0.067 0.084 | 1.24 1.29 0.061 0.000 0.079 | 1.27 0.00 0.065 0.060 0.073 | 1.44 1.20 0. 066 0.059 0.082 | 1.40 1.26 0.058 0.056 0.082 | 1.35 1.37 0.067 0.082 0.077 | 1.43 1.61 0.049 0.064 0.077 | 1.29 1. 31 0.053 0.063 0.081 | 1. 29 1. 31 0.049 0.000 0.076 | 1. 32 0.00 0. 000 0.070 0.087 | 0.00 1.43 0.054 0.060 0.086 | 1.29 1.30 0.052 0.059 0.078 | 1.33 1.28 0.053 0.057 0.090 | 1. 32 1.27 0. 049 0.067 0.074 | 1. 23 1.46 0.057 0.056 0.074 | 1.42 1.27 0.056 0.058 0.073 | 1. 33 1.35 0.052 0.058 0.074 | 1.30 1.32 0.053 0.060 0.074 | 1. 32 1.40 0.056 0.053 0.071 | 1.37 1.39 0.052 0. 041 0.080 | 1.37 1.24 0.048 0.053 0.066 | 1.33 1. 29 0.042 0.055 0.069 | 1.27 1.28 0.050 0.052 0.077 | 1.47 1.27 0.044 0.068 0.070 | 1.29 1.58 0.045 0.055 0.065 | 1.29 1.38 0.037 0.056 0.066 | 1.16 1.30 0. 038 0.047 0.075 | 1.23 1.24 0.038 0. 043 0.072 | 1.19 1.39 0.039 0.041 0.060 | 1.26 1.24 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 4500 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 26 27 28 29 30 31 32 33 34 1.20 1.33 1.43 1, 1. 1, 1. 1. 1. 1. 1. 1. 1. 1. 1. 30 30 35 23 24 34 34 24 28 37 29 43 1.43 1. 1. 1, 1, 1, 1, 1. 1. 1, 1, 1. 1, 1, 1. 1. 1, 1, 1, 30 43 40 23 24 28 28 25 38 22 21 38 30 16 29 39 38 22 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.053 16.3 33 0.037 0.070 0.059 15.5 30 0.041 0. 082 0.077 10.3 34 0. 060 0. 099 1. 32 5.6 33 1.16 1.47 1.33 7.0 30 1.20 1.61 1.31 5.8 34 1.16 1.43 TABLE 111-19 194 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Beam No. Creep Data at t = 3662 hr De f l e c t i o n ( d t ) , i n . D.Fir D.Fir 1650f 1.5E 2400f 2. OE Parallam PSL I 2325 1 | 0.053 2 I 0.073 3 I 0.000 4 I 0.068 5 I 0.059 6 1 0.054 7 | 0.062 8 I 0.070 9 1 0.069 10 | 0.061 H 1 0.071 12 | 0.049 13 | 0.055 14 | 0.050 15 | 0.000 16 | 0.056 17 | 0.053 18 | 0.055 19 | 0.052 20 | 0.058 21 | 0.059 22 | 0.053 23 | 0.054 24 | 0.058 25 | 0.055 26 | 0.050 27 | 0. 044 28 | 0.055 29 | 0. 046 30 | 0. 046 31 I 0.038 32 | 0.040 33 | 0.039 34 | 0.039 Stress p s i 3375 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 4500 | 2325 3375 4500 0.086 | 1.23 0.00 1.25 0.087 | 1.49 1.43 1.38 0.102 | 0.00 1.30 1.48 0.089 | 1.42 1.38 1.35 0.084 | 1.37 0.00 1.33 0.086 | 1.32 1.35 1.39 0.082 | 1.29 0.00 1.28 0.075 | 1.56 1.22 1.27 0.085 | 1.47 1.28 1.39 0.085 | 1.42 1.39 1.39 0.080 | 1.51 1.63 1.29 0.077 | 1.29 1.39 1.28 0.084 | 1.34 1.38 1.42 0.078 | 1.35 0.00 1.32 0.091 | 0.00 1.45 1.49 0.090 | 1.33 1.39 1.50 0.083 | 1.36 1.33 1.38 0.092 | 1.38 1.31 1.46 0.076 | 1.30 1.54 1.43 0.077 | 1.45 1.32 1.28 0.076 | 1.40 1.35 1.29 0.077 | 1.32 1.39 1.33 0.077 | 1.35 1.47 1.33 0.073 | 1.41 1.45 1.28 0.083 | 1.45 1.27 1.43 0.068 | 1.39 1.34 1.26 0.072 | 1.33 1.35 1.26 0.080 | 1.62 1.29 1.43 0.072 | 1.35 0.00 1.33 0.067 | 1.31 1.40 1.20 0.068 | 1.19 1.33 1.33 0.079 | 1.29 1.29 1.46 0.074 | 1.22 1.39 1.42 0.060 | 1.26 1.24 1.22 0.080 | 1.37 1.37 1.35 10.5 | 7.0 6.3 6.1 34 | 32 29 34 0.060 | 1.19 1.22 1.20 0.102 | 1.62 1.63 1.50 0, 0. 0, 0. 0, 0. 0. 0. 0. 0. 000 0.077 0.065 069 000 070 0.000 0.061 0.060 057 083 068 066 000 071 0.064 0.061 0.059 0.071 0. 058 0.058 061 063 055 042 055 058 053 000 056 0.057 0. 049 0. 043 0.041 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.055 17.2 32 0. 038 0.O73 0.060 16.1 29 0.041 0.083 TABLE 1 1 1 - 2 0 195 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Beam No. Creep Data at t = 5568 hr. Def l e c t i o n ( d t ) , i n . D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL I 2325 1 | 0.000 2 I 0.074 3 I 0.000 4 I 0. 070 5 I 0.059 6 I 0.054 7 1 0.064 8 I 0.072 9 I 0.069 10 | 0.062 11 1 0. 072 12 | 0.050 13 | 0.055 14 | 0. 052 15 | 0.000 16 | 0.058 17 | 0.057 18 | 0.056 19 | 0. 053 20 | 0. 060 21 I 0. 059 22 | 0. 054 23 | 0.056 24 | 0.059 25 | 0. 057 26 | 0.051 27 | 0.045 28 | 0.055 29 | 0. 046 30 | 0.046 31 I 0.038 32 | 0.040 33 | 0. 039 34 | 0. 040 Stress p s i 3375 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 4500 | 2325 3375 4500 0.087 | 0.00 0.00 1.26 0.089 | 1.51 1.44 1.41 0.103 | 0.00 1.30 1.49 0.091 | 1.46 1.46 1.38 0.085 | 1.37 0.00 1.35 0.086 | 1.32 1.35 1.39 0.083 | 1.33 0.00 1.30 0.076 | 1.60 1.24 1.29 0.086 | 1.47 1.30 1.41 0.087 | 1.44 1.39 1.43 0.080 | 1.53 1.63 1.29 0.079 | 1.32 1.39 1.32 0.085 | 1.34 1.38 1.44 0.080 | 1.41 0.00 1.36 0.091 | 0.00 1.51 1.49 0.091 | 1.38 1.41 1.52 0.083 | 1.46 1.35 1.38 0.095 | 1.40 1.36 1.51 0.076 | 1.32 1.54 1.43 0.078 | 1.50 1.34 1.30 0.076 | 1.40 1.37 1.29 0.078 | 1.35 1.39 1.34 0.078 | 1.40 1.53 1.34 0.075 | 1.44 1.47 1.32 0.083 | 1.50 1.27 1.43 0.070 | 1.42 1.37 1.30 0.072 | 1.36 1.40 1.26 0.081 | 1.62 1.32 1.45 0.074 | 1.35 0.00 1.37 0.068 | 1.31 1.42 1.21 0.068 | 1.19 1.35 1.33 0.079 | 1.29 1.29 1.46 0.075 | 1.22 1.39 1.44 0.061 | 1.29 1.24 1.24 0. 000 0.078 0.065 0. 073 0.000 0. 070 0.000 0.062 0.061 0.057 0.083 0. 068 0.066 0.000 0.074 0.065 0.062 0. 061 0.071 0. 059 0.059 0.061 0. 066 0.056 0.042 0. 056 0. 060 0.054 0. 000 0.057 0.058 0.049 0.043 0. 041 S t a t i s t i c a l Data; Mean | 0. 056 0.061 0. 081 CV% | 17.7 16.2 10.5 n | 31 29 34 Range | Low | 0.038 0.041 0.061 High | 0.074 0. 083 0.103 1.40 7.1 31 1, 1, 19 62 1.39 6.6 29 1.24 1.63 1.37 5.9 34 1.21 1.52 TABLE 111-21 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 2 Beam No. Creep Data at t = 7416 hr De f l e c t i o n ( d t ) , i n . D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL 1 Stress p s i | j 2325 3375 4500 | 2325 1 | 0.000 0.000 0.088 | 0. 00 2 I 0.076 0.078 0.090 | 1.55 3 I 0.000 0.068 0.105 | 0.00 4 I 0.070 0.074 0.092 | 1.46 5 I 0.059 0.000 0.086 | 1.37 6 1 0.054 0.071 0.087 | 1.32 7 | 0.066 0.000 0.083 | 1.38 8 I 0.072 0.062 0.076 | 1.60 9 1 0.071 0.063 0.089 | 1.51 10 | 0.063 0.056 0.088 | 1.47 11 1 0.074 0.083 0.081 | 1.57 12 | 0.050 0.068 0.080 | 1.32 13 | 0.056 0.067 0.087 | 1.37 14 | 0.053 0.000 0.080 | 1.43 15 | 0.000 0.074 0.092 | 0.00 16 | 0.059 0.066 0.093 | 1.40 17 | 0.058 0.063 0.084 | 1.49 18 | 0.057 0.063 0.097 | 1.42 19 | 0.055 0.072 0.078 | 1.38 20 | 0.061 0.061 0.080 | 1.52 21 | 0.060 0.061 0.077 | 1.43 22 | 0.055 0.062 0.078 | 1.38 23 | 0.058 0.068 0.080 | 1.45 24 | 0.061 0.057 0.075 | 1.49 25 | 0.058 0.042 0.086 | 1.53 26 | 0.051 0.058 0.070 | 1.42 27 | 0.046 0.060 0.073 | 1.39 28 | 0.057 0.056 0.082 | 1.68 29 | 0.046 0.000 0.076 | 1.35 30 | 0.046 0.058 0.069 | 1.31 31 I 0.039 0.059 0.068 | 1. 22 32 | 0.040 0.049 0.081 | 1. 29 33 | 0.040 0.044 0.076 | 1. 25 34 | 0.040 0.042 0.062 | 1.29 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 3375 4500 0.00 1.44 1, 1. 0. 1. 0. 1. 1. 1. 36 48 00 37 00 24 34 37 1.63 1.39 1. 0. 1, 1. 1. 1. 1. 1. 1. 1. 1. 1, 1. 1. 1, 1, .40 , 00 .51 .43 ,37 ,40 ,57 ,39 .42 ,41 .58 .50 ,27 ,41 .40 . 37 0.00 1.45 1.37 1.29 1.42 1.27 1.28 1.43 1.52 1. 1, 1. 1, 1. 1. 1. 1. 1. 1. 1, 1, 1. 1, 1. 1. 1, 1. 1. 1. 1, 1. 1. 1, 1. 1, 1. 1. 1. 1, 1. 39 37 40 30 29 46 44 31 33 47 36 51 55 40 54 47 33 31 34 38 32 48 30 28 46 41 23 33 50 46 27 S t a t i s t i c a l Data! Mean CV% n Range Low High 0.056 17.9 31 0.039 0.076 0.062 15.9 29 0.042 0.083 0.082 10.8 34 0.062 0.105 1.42 7.5 31 1.22 1.68 1.41 6.4 29 1.24 1.63 1.39 6.4 34 23 55 TABLEIII-22 :_ . . CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA 197 85-12-30 Stress Level 2 Beam No. Creep Data at t =11210 hr. D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir 1650f 1.5E 2400f 2.OE 1 2325 1 | 0.000 2 I 0.078 3 | 0.000 4 I 0.071 5 I 0.062 6 1 0.056 7 | 0.068 8 I 0.075 9 I 0.074 10 | 0.063 11 1 0.078 12 | 0.051 13 | 0.057 14 | 0.054 15 | 0. 000 16 | 0.062 17 | 0.058 18 | 0.058 19 | 0.055 20 | 0. 062 21 I 0.067 22 | 0.056 23 | 0.060 24 | 0.063 25 | 0.060 26 | 0.054 27 | 0.047 28 | 0.058 29 | 0.048 30 | 0.046 31 I 0.039 32 | 0.041 33 | 0.041 34 | 0.042 Stress p s i 3375 F r a c t i o n a l Creep, d t / d l Parallam D.Fir D.Fir Parallam PSL 1650f 1.5E 2400f 2.0E PSL 1 Stress p s i 4500 | 2325 3375 4500 0.090 | 0.00 0.00 1.30 0.092 | 1.59 1.48 1.46 0.108 | 0.00 1.38 1.57 0.093 | 1.48 1.58 1.41 0.088 | 1.44 0.00 1.40 0.091 | 1.37 1.42 1.47 0.086 | 1.42 0.00 1.34 0.078 | 1.67 1.30 1.32 0.092 | 1.57 1.36 1.51 0.091 | 1.47 1.39 1.49 0.083 | 1.66 1.75 1.34 0.081 | 1.34 1.43 1.35 0.090 | 1.39 1.44 1.53 0.082 | 1.46 0.00 1.39 0.094 | 0.00 1.57 1.54 0.095 | 1.48 1.48 1.58 0.086 | 1.49 1.39 1.43 0.100 | 1.45 1.40 1.59 0.079 | 1.38 1.61 1.49 0.082 | 1.55 1.41 1.37 0.078 | 1.60 1.44 1.32 0.081 | 1.40 1.45 1.40 0.081 | 1.50 1.63 1.40 0.075 | 1.54 1.53 1.32 0.088 | 1.58 1.30 1.52 0.071 | 1.50 1.44 1.31 0.075 | 1.42 1.42 1. 32 0.084 | 1.71 1.41 1.50 0.077 | 1.41 0.00 1.43 0.070 | 1.31 1.48 1.25 0.070 | 1.22 1.40 1.37 0.083 | 1.32 1.29 1.54 0.078 | 1.28 1.48 1. 50 0.062 | 1.35 1.30 1.27 0. 0. 0. 0. 0.000 0.080 0.069 0.079 0.000 0.074 0.000 0.065 0.064 0.057 ,089 ,070 ,069 ,000 0.077 0.068 0.064 0.063 0.074 0.062 0.062 0.064 0.070 0.058 0.043 0.059 061 058 ,000 ,059 0.060 0.049 0.046 0.043 0. 0. 0. 0. S t a t i s t i c a l Data: Mean CV% n Range Low High 0.058 18.5 31 0.039 0.078 0.064 16.8 29 0.043 0.089 0.084 11.2 34 0.062 0.108 1.46 8.0 31 1.22 1.71 1.45 7.2 29 1. 1, 29 75 1.42 6.7 34 1. 25 1.59 193 TABLE I I I _ 2 3 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Str e s s Level 3 Beam No. Creep Data at t = 1 min D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir 1650f 1.5E 2400f 2.OE I 2575 1 | 0.056 2 I 0.051 3 | 0.065 4 I 0.055 5 I 0.047 6 1 0.054 7 | 0.047 8 I 0.048 9 1 0.050 10 | 0.047 11 1 0.047 12 | 0.047 13 | 0.047, 14 | 0.048 15 | 0.046 16 | 0.042 17 | 0.046 18 | 0.047 19 | 0.044 20 | 0.033 21 | 0.044 22 | 0.039 23 | 0.046 24 | 0.057 25 | 0.040 26 | 0.036 27 | 0.038 28 | 0.036 29 | 0.041 30 | 0.041 31 | 0.033 32 | 0.037 33 | 0.034 34 | 0.037 Stress p s i 3750 F r a c t i o n a l Creep, d t / d l Parallam D.Fir D.Fir Parallam PSL 1650f 1.5E 2400f 2.0E PSL 1 Stress p s i 5000 2575 3750 5000 0.071 1.00 1.00 1.00 0.074 1.00 1.00 1.00 0.069 1.00 1.00 1.00 0.073 1.00 1.00 1. 00 0.071 1.00 1.00 1.00 0.070 1.00 1.00 1.00 0.070 1.00 1. 00 1.00 0.072 1.00 1.00 1.00 0.070 1.00 1.00 1.00 0.067 1.00 1.00 1.00 0.069 1.00 1.00 1.00 0.070 1.00 1.00 1.00 0.067 1.00 1.00 1.00 0.068 1.00 1.00 1.00 0.067 1.00 1.00 1.00 0.062 1.00 1.00 1.00 0.069 1.00 1.00 1.00 0.069 1.00 1.00 1.00 0.066 1.00 1.00 1.00 0.064 1.00 1.00 1.00 0.062 1.00 1.00 1.00 0.065 1.00 1.00 1.00 0.062 1.00 1.00 1.00 0.064 1.00 1.00 1.00 0.062 1.00 1.00 1.00 0.061 1. 00 1.00 1.00 0.063 1.00 1.00 1.00 0.060 1.00 1.00 1.00 0.059 1.00 1.00 1.00 0.057 1.00 1.00 1.00 0.060 1.00 1.00 1.00 0.055 1.00 1.00 1.00 0.055 1.00 1.00 1.00 0.057 1.00 1.00 1.00 0, 0 0, 0 0 0 0, 0 0 0.063 0.069 0.059 0.052 0.058 0.054 051 052 055 051 047 058 054 052 054 0.050 0.048 0.061 0. 048 0.052 0.048 048 044 047 045 047 047 044 044 044 048 044 042 0. 037 S t a t i s t i c a l Data: Mean CV% n Range Low Hicrh 0.045 16.5 34 0.033 0.065 0.051 13.1 34 0.037 0.069 0.065 8.1 34 0.055 0.074 1.00 0.0 34 1, 1, 00 00 1.00 0.0 34 1, 1. 00 00 1.00 0.0 34 1.00 1. 00 TABLE I11-24 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Str e s s Level 3 Beam No. Creep Data at t De f l e c t i o n ( d t ) , i n . 28 hr, D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL 1 Stress p s i ! Stress p s i j 2575 3750 5000 | 2575 3750 1 1 0.059 0.069 0.080 | 1.05 1.10 2 I 0.058 0.077 0.080 | 1.14 1.12 3 I 0.067 0.061 0.079 | 1.03 1.03 4 i 0.057 0.056 0.080 | 1.04 1.08 5 I 0.050 0.063 0.075 | 1.06 1.09 6 | 0.059 0.057 0.076 | 1.09 1.06 7 i 0.049 0.052 0.074 | 1.04 1. 02 8 I 0.049 0.054 0.079 | 1.02 1.04 9 I 0.051 0.059 0.076 | 1.02 1.07 10 | 0.050 0.053 0.070 | 1.06 1.04 11 1 0.048 0.050 0.073 | 1.02 1.06 12 | 0.048 0.062 0.071 | 1.02 1.07 13 | 0.048 0.060 0.072 | 1.02 1.11 14 | 0.050 0.055 0.073 | 1.04 1.06 15 | 0.049 0.058 0.074 | 1.07 1. 07 16 | 0.045 0.054 0.068 | 1.07 1.08 17 | 0. 048 0.053 0.074 | 1.04 1.10 18 | 0.050 0.067 0^074 | 1.06 1.10 19 | 0.045 0.056 0.069 | 1.02 1.17 20 | 0.035 0.055 0.070 | 1.06 1.06 21 I 0.048 0.051 0.066 | 1.09 1.06 22 | 0.042 0.049 0.072 | 1.08 1.02 23 | 0.047 0.047 0.066 | 1.02 1.07 24 | 0.064 0.049 0.068 | 1.12 1. 04 25 | 0.041 0.045 0.071 | 1.03 1.00 26 | 0.038 0.051 0.066 | 1.06 1.09 27 | 0.041 0.050 0.065 | 1.08 1.06 28 | 0.039 0.044 0.066 | 1.08 1.00 29 | 0.042 0.045 0.061 | 1.02 1.02 30 | 0.044 0.047 0.060 | 1.07 1.07 31 I 0.035 0.052 0.064 | 1.06 1.08 32 | 0.039 0.046 0.059 | 1.05 1.05 33 | 0.037 0.044 0.058 | 1.09 1.05 34 | 0.040 0.038 0.063 | 1.08 1.03 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL 5000 1.13 1.08 1. 1. 1, 1, 1. 1, 1, 1. 1, 1, 1, 1, 1, 1, 1. 1, 1, 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1, 1. 1. 1. 1. 14 10 06 09 06 10 09 04 06 01 07 07 10 10 07 07 05 09 06 11 06 06 15 08 03 10 03 05 07 07 05 11 S t a t i s t i c a l Data: Mean CV% . n Range Low High 0.047 16.6 34 0. 035 0.067 0.054 14.8 34 0. 038 0.077 0.070 8.8 34 0.058 0.080 1.06 2.8 34 1.02 1.14 1.06 3.3 34 1.00 1.17 1.08 2.8 34 1.01 1.15 200 TABLE IU-25 85-12-30 CODE APPROVAL LOAD.DURATION STUDY BEAM DEFORMATION DATA Stress Level 3 Creep Data at t = 100 hr Beam | De f l e c t i o n ( d t ) . i n . | F r a c t i o n a l Creep, d t / d l No. | D.Fir D.Fir Parallam | D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL | 1650f 1.5E 2400f 2.0E PSL Stress p s i 1 Stress p s i 2575 3750 5000 | 2575 3750 5000 1 | 0.061 0.069 0.082 | 1.09 1.10 1.15 2 I 0.061 0.081 0.084 | 1.20 1.17 1.14 3 I 0.068 0.061 0.079 | 1.05 1.03 1.14 4 I 0.057 0.059 0.083 | 1.04 1.13 1.14 5 I 0.050 0.066 0.078 | 1.06 1.14 1.10 6 I 0.062 0.059 0.078 | 1. 15 1.09 1.11 7 j 0.051 0.052 0.075 | 1.09 1.02 1.07 8 I 0.052 0.056 0.080 | 1.08 1.08 1.11 9 I 0.053 0.061 0.080 | 1.06 1.11 1.14 10 | 0.052 0.056 0.073 | 1.11 1.10 1.09 11 1 0.050 0.051 0.076 | 1.06 1.09 1.10 12 | 0.050 0.066 0.075 | 1.06 1.14 1.07 13 | 0.050 0.062 0.075 | 1.06 1.15 1.12 14 I 0.053 0.057 0.075 | 1.10 1.10 1.10 15 | 0.052 0.060 0.077 | 1.13 1.11 1.15 16 | 0. 047 0.057 0.072 | 1.12 1.14 1.16 17 | 0. 048 0.055 0.077 | 1.04 1.15 1.12 18 | 0.053 0.068 0.077 | 1.13 1.11 1.12 19 | 0.047 0.060 0.071 | 1.07 1.25 1.08 20 | 0.036 0.059 0.071 | 1.09 1.13 1.11 21 | 0.050 0.052 0.068 | 1.14 1.08 1.10 22 | 0.043 0.050 0.075 | 1.10 1.04 1.15 23 | 0.048 0.050 0.068 | 1.04 1.14 1.10 24 | 0. 068 0.050 0.070 | 1.19 1.06 1.09 25 | 0.043 0.047 0.072 | 1.08 1.04 1.16 26 | 0.038 0.052 0.068 | 1.06 1.11 1.11 27 | 0.041 0.052 0.067 | 1.08 1.11 1.06 28 | 0.041 0.046 0.068 | 1.14 1.05 1.13 29 | 0.042 0.047 0.063 | 1.02 1.07 1.07 30 | 0.045 0.048 0.063 | 1.10 1.09 1.11 31 I 0.036 0.053 0.066 | 1.09 1.10 1.10 32 | 0.040 0.046 0.060 | 1.08 1.05 1.09 33 | 0. 038 0.045 0.059 | 1.12 1.07 1.07 34 | 0.040 0.040 0.066 | 1.08 1.08 1.16 S t a t i s t i c a l Data: Mean 0.049 0.056 0.073 | 1.09 1.10 1.11 CV% 17.2 15.0 8.9 | 3.7 4.2 2.6 n 34 34 34 | 34 34 34 Range j Low 0.036 0.040 0.059 | 1.02 1.02 1.06 High 0.068 0.081 0.084 | 1.20 1.25 1.16 TABLE 111-26 201 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 3 Beam No. Creep Data at t D e f l e c t i o n ( d t ) , i n . 288 hr. D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i i 2575 3750 5000 | 2575 1 1 0.064 0.000 0.088 | 1.14 2 I 0. 067 0.087 0.086 | 1.31 3 | 0.073 0.064 0.083 | 1.12 4 I 0.061 0.063 0.087 | 1.11 5 I 0.052 0.069 0.080 | 1.11 6 1 0.065 0. 062 0.081 | 1.20 7 | 0.052 0.054 0.078 | 1.11 8 I 0.054 0.061 0.086 | 1.12 9 I 0.058 0.065 0.088 | 1.16 10 | 0.054 0. 062 0.077 | 1.15 11 1 0.054 0.053 0.079 | 1.15 12 | 0.054 0.072 0.078 | 1.15 13 | 0.054 0.065 0.080 | 1.15 14 | 0.056 0. 060 0.078 | 1.17 15 | 0.053 •' 0.063 0.081 | 1.15 16 | 0.052 0.063 0.075 | 1.24 17 | 0.052 0.058 0.080 | 1.13 18 | 0.058 0.076 0.081 | 1.23 19 | 0.050 0. 062 0.074 | 1.14 20 | 0.038 0. 063 0.075 | 1.15 21 | 0.053 0. 054 0.071 | 1.20 22 | 0.046 0.053 0.078 | 1.18 23 | 0.051 0.052 0.070 | 1.11 24 | 0.075 0.051 0.072 | 1.32 25 | 0.045 0.053 0.076 | 1.13 26 | 0.041 0.054 0.071 | 1.14 27 | 0.045 0. 056 0.070 | 1.18 28 | 0.042 0. 047 0.073 | 1.17 29 | 0.044 0.050 0.065 | 1.07 30 | 0.049 0.051 0.065 | 1.20 31 I 0.037 0. 054 0.067 | 1.12 32 | 0. 045 0.048 0.063 | 1.22 33 | 0.041 0. 047 0.061 | 1. 21 34 | 0.042 0.043 0.070 | 1.14 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 3750 5000 0.00 1.26 1.08 1.21 1.19 1. 1. 1, 1. 1, 1, 1, 1. 1. 15 06 17 18 22 13 24 20 15 1.17 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 26 21 25 29 21 12 10 18 09 18 15 19 07 14 16 13 09 12 16 24 16 20 19 13 16 11 19 26 1.15 1.14 1.11 1.19 1.15 1.21 1.21 1.16 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 17 12 17 15 20 13 13 23 16 11 22 10 14 12 15 11 23 S t a t i s t i c a l Data; Mean CV% n Range Low High 0.052 17.7 34 0.037 0.075 0.059 15.6 33 0. 043 0.087 0. 076 9.5 34 0.061 0. 088 1.16 4.7 34 1.07 1.32 1.17 5.0 33 1.06 1. 29 1.16 3.7 34 1.10 1.26 TABLE 111-27 202 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 3 Creep Data at t = 529 hr Beam 1 D e f l e c t i o n ( d t ) , i n . | F r a c t i o n a l Creep, d t / d l No. | D.Fir D.Fir Parallam | D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL | 1650f 1.5E 2400f 2.0E PSL Stress p s i i Stress p s i 2575 3750 5000 | 2575 3750 5000 1 | 0.068 0.000 0.094 | 1.21 0.00 1.32 2 I 0.076 0. 098 0.090 | 1.49 1.42 1.22 3 ! 0.085 0.072 0.087 | 1.31 1.22 1.26 4 I 0.068 0.068 0.095 | 1.24 1.31 1.30 5 I 0.059 0.074 0.084 | 1.26 1.28 1.18 6 1 0.071 0.068 0.084 | 1.31 1.26 1.20 7 | 0.054 0.056 0.081 | 1.15 1.10 1.16 8 I 0.064 0.067 0.093 | 1.33 1.29 1.29 9 1 0.062 0.071 0.094 | 1.24 1.29 1.34 10 | 0.057 0.070 0.079 | 1.21 1.37 1.18 11 1 0.060 0.056 0.085 | 1.28 1.19 1.23 12 | 0.056 0.080 0.080 | 1.19 1.38 1.14 13 | 0. 060 0.071 0.083 | 1.28 1.31 1.24 14 | 0.061 0.062 0.081 | 1.27 1.19 1.19 15 ! 0.057 0.066 0.087 | 1.24 1.22 1.30 16 | 0.054 0.067 0.081 | 1.29 1.34 1.31 17 | 0.058 0.064 0.085 | 1.26 1.33 1.23 18 | 0.064 0.078 0.086 | 1.36 1.28 1.25 19 | 0.056 0.065 0.078 | 1.27 1.35 1.18 20 | 0.041 0.071 0.081 | 1.24 1.37 1.27 21 | 0.058 0.056 0.075 | 1.32 1.17 1.21 22 | 0.052 0. 060 0.082 | 1.33 1.25 1.26 23 | 0.056 0. 053 0.073 | 1.22 1.20 1.18 24 | 0.086 0.055 0.077 | 1.51 1.17 1.20 25 | 0.048 0.058 0.080 | 1.20 1.29 1.29 26 | 0. 045 0.059 0.074 | 1.25 1.26 1.21 27 j 0.048 0.059 0.073 | 1.26 1.26 1.16 28 | 0.049 0.053 0.076 | 1.36 1.20 1.27 29 | 0.045 0.056 0.067 | 1.10 1.27 1.14 30 | 0.053 0.056 0.068 | 1.29 1.27 1.19 31 I 0.041 0.058 0.072 | 1.24 1.21 1.20 32 j 0.049 0.052 0.066 | 1.32 1.18 1.20 33 j 0.044 0.049 0.064 | 1.29 1.17 1.16 34 | 0. 044 0. 046 0.072 | 1.19 1.24 • 1.26 S t a t i s t i c a l Data: Mean | 0.057 0.063 0.080 | 1.27 1.26 1.23 CV% 19.4 16.4 10.2 | 6.4 5.8 4.5 n 34 33 34 | 34 33 34 Range j Low | 0.041 0. 046 0.064 | 1.10 1.10 1.14 High ! 0.086 0.098 0.095 | 1.51 1.42 1.34 XAiJLit I I I - 2 8 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 3 Beam No. Creep Data at t = 1200 hr. D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir Parallam D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL 1650f 1.5E 2400f 2.0E PSL Stress p s i Stress p s i 2575 3750 5000 2575 3750 5000 0.069 0.000 0.096 1.23 0.00 1.35 0.082 0.109 0.094 | 1.61 1.58 1.27 0. 088 0.071 0.088 ! 1.35 1.20 1.28 0.068 0.000 0.096 1.24 0.00 1.32 0.000 0. 079 0.086 | 0.00 1.36 1.21 0. 074 0. 068 0.086 1.37 1.26 1.23 0.000 0. 057 0.083 0.00 1.12 1.19 0. 064 0. 068 0.094 | 1.33 1.31 1.31 0.064 0.073 0.097 j 1.28 1.33 1.39 0.000 0.071 0.082 0.00 1.39 1.22 0.060 0. 057 0.086 1.28 1.21 1.25 0.057 0.082 0.082 1.21 1.41 1.17 0.062 0.071 0.085 1.32 1.31 1.27 0.061 0. 063 0.083 | 1.27 1.21 1. 22 0.059 0. 068 0.089 ! 1.28 1.26 1.33 0.057 0.070 0.083 | 1.36 1.40 1.34 0.057 0. 066 0.088 1.24 1.38 1.28 0.067 0.084 0.087 1.43 1.38 1.26 0.056 0.069 0.079 j 1.27 1.44 1.20 0. 041 0.071 0.081 j 1.24 1.37 1.27 0. 060 0.059 0.076 1.36 1.23 1.23 0. 052 0.060 0.086 1.33 1.25 1.32 0.056 0.054 0.074 1.22 1.23 1.19 0.092 0.055 0.077 1.61 1.17 1.20 0.049 0.058 0.082 1.23 1.29 1.32 0. 045 0.059 0.076 I 1.25 1.26 1. 25 0.048 0. 060 0.073 1.26 1.28 1.16 0. 050 0.053 0.079 1.39 1.20 1.32 0. 048 0.057 0.067 1.17 1.30 1.14 0.057 0. 056 0.069 1.39 1.27 1.21 0.041 0.063 0.073 j 1.24 1.31 1.22 0. 050 0.052 0.068 | 1.35 1.18 1.24 0. 045 0.049 0.064 | 1.32 1.17 1.16 0. 045 0.046 0.077 1.22 1.24 1.35 F r a c t i o n a l Creep, d t / d l 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 26 27 28 29 30 31 32 33 34 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.059 21.5 31 0.041 0. 092 0.065 18.9 32 0.046 0.109 0.082 10.4 34 0.064 0. 097 1.31 7.8 31 1.17 1.61 1.29 7.4 32 1.12 1.58 1.25 5.0 34 1.14 1.39 T A B l i t , H I - 2 9 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 3 Beam No. Creep Data at t = 2325 hr D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir 1650f 1.5E 2400f 2.0E 1 2575 1 | 0.072 2 I 0.000 3 | 0.000 4 I 0.071 5 I 0.000 6 1 0.078 7 I 0.000 8 I 0.066 9 1 0.066 10 | 0.000 11 1 0.062 12 | 0.058 13 | 0.067 14 | 0.064 15 | 0.062 16 | 0.062 17 | 0.063 18 | 0.073 19 | 0.058 20 | 0.041 21 | 0.062 22 | 0.054 23 | 0.060 24 | 0.103 25 | 0.052 26 | 0.047 27 | 0.052 28 | 0.051 29 | 0.049 30 | 0.059 31 I 0.041 32 | 0.052 33 | 0.046 34 | 0.047 Stress p s i 3750 F r a c t i o n a l Creep, d t / d l Parallam j PSL | D.Fir 1650f 1.5E D.Fir 2400f 2.0E Parallam PSL 1 Stress p s i 5000 | 2575 3750 5000 0.101 | 1 29 0 00 1 42 0.099 | 0 00 0 00 1 34 0.093 | 0 00 1 22 1 35 0.101 | 1 29 0 00 1 38 0.089 | 0 00 1 45 1 25 0.090 | 1 44 0 00 1 29 0.086 | 0 00 1 14 1 23 0.101 | 1 37 1 33 1 40 0.102 | 1. 32 1 33 1 46 0.086 | 0 00 1 49 1 28 0.090 | 1 32 1 21 1 30 0.085 | 1 23 1 50 1 21 0.089 | 1 43 1 35 1 33 0.086 | 1 33 1 33 1 26 0.093 | 1 35 1 31 1 39 0.087 | 1 48 1 44 1 40 0.091 | 1 37 1 40 1 32 0.091 | 1 55 1 46 1 32 0.085 | 1 32 1 48 1 29 0.086 | 1 24 1 44 1 34 0.079 | 1 41 1 23 1 27 0.091 | 1 38 1 27 1 40 0.078 | 1 30 1 27 1 26 0.081 | 1 81 1 21 1 27 0.085 | 1 30 1 31 1 37 0.079 | 1 31 1 30 1 30 0.077 | 1 37 1 30 1 22 0.082 | 1 42 1 25 1 37 0.069 | 1 20 1 32 1 17 0.072 | 1 44 1 30 1 26 0.076 | 1 24 1 38 1 27 0.071 | 1 41 1 20 1 29 0.066 | 1 35 1 19 1 20 0.081 | 1 27 1 30 1 42 000 000 072 000 084 000 0.058 0.069 0.073 0.076 0.057 0.087 0.073 069 071 072 067 089 0.071 0.075 059 061 056 057 059 061 061 055 058 057 066 053 050 048 0. 0. 0. 0, 0, 0. 0, 0, 0. 0. 0. 0. 0, 0, 0, 0, 0, 0, 0, S t a t i s t i c a l Data: Mean CV% n Range Low High 0.060 21.1 29 0.041 0.103 0.065 16.1 30 0.048 0.089 0.086 10.8 34 0.066 0.102 1.36 8.6 29 1.20 1.81 1.32 7.4 30 1.14 1.50 1.31 5.4 34 1.17 1.46 TABLE IH-30 2Qb 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 3 Beam No. Creep Data at t = 3662 hr. D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir 1650f 1.5E 2400f 2.OE 1 2575 1 | 0.075 2 i 0. 000 3 I 0. 000 4 I 0.075 5 I 0.000 6 I 0.081 7 | 0.000 8 I 0.070 9 I 0.069 10 | 0.000 11 1 0.065 12 | 0.060 13 | 0.069 14 | 0. 068 15 | 0.063 16 | 0. 065 17 1 0.063 18 | 0.077 19 | 0.059 20 | 0.042 21 | 0.065 22 | 0.057 23 | 0.061 24 | 0.109 25 | 0.053 26 | 0.048 27 | 0.052 28 | 0.051 29 | 0.050 30 | 0.060 31 I 0.042 32 | 0.057 33 | 0.048 34 | 0.047 Stress p s i 3750 F r a c t i o n a l Creep, d t / d l Parallam D.Fir D.Fir Parallam PSL 1650f 1.5E 2400f 2.0E PSL 1 Stress p s i 5000 | 2575 3750 5000 0.106 | 1.34 0.00 1.49 0.101 0.00 0.00 1.36 0.094 0.00 1.27 1.36 0.105 | 1.36 0.00 1.44 0.092 | 0.00 1.50 1.30 0.093 | 1.50 0.00 1.33 0.089 | 0.00 1.14 1.27 0.106 | 1.46 1.38 1.47 0.104 | 1.38 1.38 1.49 0.087 j 0.00 1.53 1.30 0.093 | 1.38 1.26 1.35 0.087 | 1.28 1.50 1.24 0.092 | 1.47 1.41 1.37 0.088 | 1.42 1.37 1.29 0.099 I 1.37 1.35 1.48 0.089 | 1.55 1.50 1.44 0.095 | 1.37 1.48 1.38 0.094 | 1.64 1.48 1.36 0.085 | 1.34 1.54 1.29 0.089 | 1.27 1.44 1.39 0.082 | 1.48 1.29 1.32 0.094 | 1.46 1.29 1.45 0.079 | 1.33 1.32 1.27 0.083 | 1.91 1.30 1.30 0.087 | 1.32 1.38 1.40 0.081 | 1.33 1.34 1.33 0.077 | 1.37 1.34 1.22 0.086 | 1.42 1.27 1.43 0.071 | 1.22 1.39 1.20 0.075 | 1.46 1.32 1.32 0.078 | 1.27 1.42 1.30 0.073 | 1.54 1.23 1.33 0.068 | 1.41 1.24 1.24 0.083 | 1.27 1.32 1.46 0. 000 0.000 0.075 0.000 0.087 0. 000 058 072 076 078 0.059 0.087 076 071 073 075 071 090 074 075 062 062 058 0.061 0.062 063 063 056 061 058 068 0.054 0.052 0.049 0. 0, 0. 0, S t a t i s t i c a l Data: Mean CV% n Range Low High 0.062 22.1 29 0.042 0.109 0.068 15.7 30 0. 049 0. 090 0.088 11.2 34 0. 068 0.106 1.41 9.6 29 1.22 1.91 1.37 7.3 30 1.14 1.54 1.35 6.0 34 1.20 1.49 TABLE III-31 206 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 3 Beam No. Creep Data at t = 5568 hr D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL 1 Stress p s i | j 2575 3750 5000 | 2575 1 | 0.075 0. 000 0.108 | 1.34 2 I 0.000 0. 000 0.102 | 0.00 3 I 0.000 0.076 0.095 | 0.00 4 I 0.077 0.000 0.107 | 1.40 5 I 0. 000 0.088 0.094 | 0.00 6 1 0.082 0.000 0.094 | 1.52 7 | 0.000 0.060 0.089 | 0.00 8 I 0.072 0.076 0.108 | 1.50 9 I 0.071 0.080 0.108 | 1.42 10 | 0.000 0.080 0.089 | 0.00 11 1 0.065 0.059 0.094 | 1.38 12 | 0. 060 0.089 0.089 | 1.28 13 | 0.070 0.076 0.093 | 1.49 14 | 0.068 0.072 0.090 | 1.42 15 | 0.064 0.075 0.100 | 1.39 16 | 0.065 0.076 0.090 | 1.55 17 | 0.065 0.072 0.097 | 1.41 18 | 0.078 0.092 0.096 | 1.66 19 | 0.060 0.075 0.088 | 1.36 20 | 0. 044 0. 078 0.091 | 1.33 21 | 0. 067 0.062 0.083 | 1. 52 22 | 0.058 0.064 0.095 | 1.49 23 | 0. 064 0.058 0.080 | 1.39 24 | 0.112 0.061 0.083 | 1.96 25 | 0.054 0.063 0.089 | 1.35 26 | 0.048 0.065 0.081 | 1.33 27 | 0.054 0.063 0.078 | 1.42 28 | 0.053 0.056 0.088 | 1.47 29 | 0.051 0. 062 0.072 | 1.24 30 | 0.063 0.059 0.075 | 1.54 31 | 0.043 0. 068 0.079 | 1.30 32 | 0.058 0.056 0.075 | 1.57 33 | 0.049 0.053 0.068 | 1.44 34 | 0. 048 0.050 0.085 | 1. 30 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i 3750 5000 0.00 0.00 1.29 0.00 1.52 0. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 1. 00 18 46 45 57 26 53 41 38 39 52 50 51 56 50 29 33 32 1.30 1.40 1.38 1.34 1.27 1.41 1. 1. 1, 1. 1, 34 42 27 26 35 1.52 1.38 1.38 1.47 1.32 .1. 1. 1. 1. 1. 34 27 50 54 33 1.36 1.27 1. 1. 1. 1. 1. 1. 1. 39 32 49 45 41 39 33 1.42 1.34 1, 1, 1, 1, 1, 46 29 30 44 33 1.24 1.47 1. 1, 1. 1, 1. 1, 22 32 32 36 24 49 S t a t i s t i c a l Data: Mean CV% n Range Low High 0.063 22.0 29 0. 043 0.112 0.069 16.0 30 0.050 0.092 0.090 11.5 34 0. 068 0.108 1.44 9.7 29 24 96 1.39 7.5 30 1.18 1.57 1.37 6.3 34 1. 1. 22 54 TABLE III-32 207 85-12-30 CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 3 Beam No. Creep Data at t = 7416 hr, D e f l e c t i o n ( d t ) , i n . D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL Stress p s i I 2575 1 | 0.076 2 I 0.000 3 | 0. 000 4 I 0.078 5 I 0.000 6 1 0.084 7 I 0.000 8 I 0.073 9 1 0.073 10 | 0. 000 11 1 0.067 12 | 0.062 13 | 0.071 14 | 0.070 15 | 0.065 16 | 0.068 17 | 0. 066 18 | 0. 082 19 | 0.062 20 | 0. 044 21 | 0.067 22 | 0. 059 23 | 0.066 24 | 0.117 25 | 0.054 26 | 0.049 27 | 0.055 28 | 0.055 29 | 0.051 30 | 0.063 31 | 0. 045 32 | 0. 059 33 | 0.050 34 | 0.048 F r a c t i o n a l Creep, d t / d l D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.OE PSL Stress p s i 3750 5000 | 2575 3750 5000 0.000 0.111 | 1.36 0.00 1.56 0. 000 0.103 | 0.00 0. 00 1.39 0.078 0.096 | 0.00 1.32 1.39 0.000 0.109 | 1.42 0.00 1.49 0.088 0.095 | 0.00 1.52 1.34 0. 000 0.094 | 1.56 0.00 1.34 0.060 0.091 | 0. 00 1. 18 1.30 0.078 0.110 | 1.52 1.50 1.53 0.089 0.114 | 1.46 1.62 1.63 0.082 0.092 | 0.00 1.61 1.37 0.060 0.096 | 1.43 1.28 1.39 0.091 0.089 | 1.32 1.57 1.27 0.078 0.095 | 1.51 1.44 1.42 0. 072 0.091 | 1.46 1.38 1.34 0.077 0.102 | 1.41 1.43 1.52 0.077 0.091 | 1.62 1.54 1.47 0.073 0.099 | 1.43 1.52 1.43 0. 094 0.099 | 1.74 1. 54 1.43 0.076 0.090 | 1.41 1.58 1.36 0.080 0.092 | 1. 33 1.54 1.44 0.063 0.084 | 1. 52 1.31 1.35 0.066 0.097 | 1.51 1.38 1.49 0. 062 0.082 | 1.43 1.41 1.32 0.062 0.085 | 2.05 1. 32 1.33 0.065 0.091 | 1.35 1.44 1.47 0. 065 0.083 | 1.36 1.38 1.36 0.064 0.078 | 1.45 1.36 1.24 0. 057 0.089 | 1.53 1. 30 1.48 0.063 0.073 | 1.24 1.43 1.24 0.059 0.077 | 1.54 1. 34 1.35 0. 069 0.080 | 1.36 1.44 1.33 0.056 0.075 | 1.59 1.27 1.36 0.053 0.069 | 1.47 1.26 1.25 0. 051 0.086 | 1. 30 1. 38 1.51 S t a t i s t i c a l Data: Mean CV%, n Range Low High 0.065 22.7 29 0. 044 0.117 0. 070 16.6 30 0. 051 0. 094 0. 091 12.0 34 0.069 0.114 1.47 10.5 29 1.24 2.05 1.42 8.1 30 1.18 1.62 1.40 6.8 34 1.24 1.63 TABLE 111-33 86- ^ I G CODE APPROVAL LOAD DURATION STUDY BEAM DEFORMATION DATA Stress Level 3 Creep Data at t =11210 hr Beam | D e f l e c t i o n ( d t ) , i n . | F r a c t i o n a l Creep, d t / d l No. | D.Fir D.Fir Parallam | D.Fir D.Fir Parallam 1650f 1.5E 2400f 2.0E PSL | 1650f 1.5E 2400f 2.0E PSL Stress p s i 1 Stress p s i 2575 3750 5000 | 2575 3750 5000 1 | 0.078 0.000 0.115 | 1.39 0.00 1.62 2 I 0.000 0. 000 0.107 | 0.00 0.00 1.45 3 j 0.000 0.079 0.096 | 0.00 1. 34 1.39 4 j 0.079 0.000 0.112 | 1.44 0.00 1. 53 5 I 0.000 0.097 0.096 | 0.00 1.67 1. 35 6 j 0. 088 0.000 0.097 | 1.63 0.00 1.39 7 j 0. 000 0. 061 0.093 | 0. 00 1.20 1. 33 8 | 0. 077 0.079 0.111 | 1.60 1.52 1.54 9 | 0.076 0.089 0.116 | 1.52 1.62 1.66 10 | 0.000 0.084 0.092 | 0.00 1.65 1.37 11 1 0. 070 0.063 0.098 | 1.49 1.34 1.42 1 2 | 0.063 0.092 0.092 | 1.34 1.59 1.31 13 | 0.073 0.080 0.098 | 1.55 1.48 1.46 1 4 0.071 0.074 0.092 | 1.48 1.42 1.35 15 | 0. 066 0.079 0.104 | 1.43 1.46 1.55 16 | 0.070 0.080 0.094 | 1.67 1.60 1.52 17 | 0.068 0.075 0.102 | 1.48 1.56 1.48 . 18 | 0.083 0. 096 0.101 | 1.77 1.57 1.46 19 | 0.062 0.078 0.090 | 1.41 1.63 1.36 20 j 0.044 0.082 0.095 | 1.33 1.58 1.48 21 0.069 0.066 0.086 | 1.57 1.37 1.39 22 | 0. 061 0.067 0.100 | 1.56 1.40 1.54 23 j 0. 068 0. 062 0.085 | 1.48 1.41 1. 37 24 0.128 0.064 0.000 | 2.25 1.36 0.00 25 0.056 0.067 0.093 | 1.40 1.49 1.50 26 0.050 0. 066 0.085 | 1.39 1.40 1.39 27 0.056 0.067 0.080 | 1.47 1.43 1.27 28 0.058 0.057 0.092 | 1.61 1.30 1.53 29 0.053 0.065 0.074 | 1.29 1.48 1.25 30 0. 067 0.061 0.078 | 1.63 1.39 1.37 31 I 0. 045 0.070 0.082 | 1.36 1.46 1.37 32 I 0.060 0.059 0.076 | 1.62 1.34 1.38 3 3 | 0. 052 0.055 0.071 | 1.53 1.31 1.29 34 | 0.049 0.052 0.089 | 1. 32 1.41 1.56 S t a t i s t i c a l Data: Mean | 0.067 0.072 0.094 | 1.52 1.46 1.43 CV% | 24.4 16.7 12.1 | 12. 0 8.2 7.0 n | 29 30 33 | 29 30 33 Range | | Low | 0.044 0.052 0.071 | 1.29 1.20 1.25 High 0.128 0.097 0.116 | 2.25 1.67 1.66 

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