Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

SEITRON SEIsmic elecTRONic handbook : a knowledge based systems approach to structural steel design Siu, Lillian S. F. 1993

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata


831-ubc_1993_fall_siu_lillian.pdf [ 6.19MB ]
JSON: 831-1.0050495.json
JSON-LD: 831-1.0050495-ld.json
RDF/XML (Pretty): 831-1.0050495-rdf.xml
RDF/JSON: 831-1.0050495-rdf.json
Turtle: 831-1.0050495-turtle.txt
N-Triples: 831-1.0050495-rdf-ntriples.txt
Original Record: 831-1.0050495-source.json
Full Text

Full Text

SEITRONSEIsmic ElecTRONic HandbookA Knowledge Based Systems Approach to Structural Steel DesignByLillian S.F. SiuB.A.Sc. (Civil) The University of British Columbia 1990A THESIS SUBMITTED IN PARTIAL FULFILLMENT OFTHE REQUIREMENTS FOR THE DEGREE OFMASTERS OF APPLIED SCIENCEDepartment of Civil EngineeringWe accept this thesis as conforming to the required standardTHE UNIVERSITY OF BRITISH COLUMBIANovember 1993© Lillian S.F. Siu, 1993In presenting this thesis in partial fulfilment of the requirements for an advanceddegree at the University of British Columbia, I agree that the Library shall make itfreely available for reference and study. I further agree that permission for extensivecopying of this thesis for scholarly purposes may be granted by the head of mydepartment or by his or her representatives. It is understood that copying orpublication of this thesis for financial gain shall not be allowed without my writtenpermission.Department of ^c 1 I_^0,40 itk-,-; The University of British ColumbiaVancouver, CanadaDate^2 6C-P-C "i5DE-6 (2/88)AbstractThe Canadian steel code, CAN3-S16.1-M89, has become increasingly complex with theintroduction of new seismic provisions, Clause 27, in its 1989 edition of the Handbook of SteelDesign. The implementation of these provisions is meant to provide the necessary ductility andredundancy requirements for the basic types of steel frame construction. Prior to the 1989changes, it was reasoned within the industry that the inherent mechanical properties of steel andthe standard design practices provided adequate ductile frame behaviour. However, testsperformed in the 1970's and 80's have shown successful behaviour of some frames and lessdesirable characteristics in other.The purpose of Clause 27 is to quantify design practices such that an adequate level of ductilityand redundancy is reached for the basic types of steel frames.Further to the concept of steel member design, there are numerous software packages availablefor structural analysis using finite elements, static and dynamic elastic theory; however, there arevery few design packages which transpose the forces from the analysis software into quantifiableresults of beam, columils and connections.The objectives of this thesis is to clarify and illustrate the design principles as stated in Clause 27of the HSC Edition 91 and to expand the engineer's toolkit with elemental design tools. This isdone in three ways:1^Provide an electronic reference system for Clause 27, along with electronic linksto commentary and referencesii2^Quantify the critical elements of each frame system and provide thecorresponding code design requirements through the use of graphics.3^Provide design templates as engineering design tools which utilize Clause 27other CAN3 -S 16. 1-M89 design requirements.The approach taken in the design of SEITRON, (from SEIsmic ElecTRONic Handbook), is toutilize the present state-of-the-art computer technology in order to provide the qualifyingrelationships and links that are inherent in the new code. Also, the creation of a WINDOWSenvironment coupled with the use of graphics is intended to effectively illustrate the application ofthe code with respect to the particular frame element and frame type.In terms of expanding the engineer's toolkit, SEITRON bridges this gap with structuredspreadsheet templates which incorporate the CAN3-S16.1-M91 steel design code. The resultantforces from structural analysis can be placed in the templates for automatic or user definedmember selection and elemental strength and stability checks. The structured templates increasethe engineers efficiency and decreases the time spent on design.The development of SEITRON promises many benefits to the steel design industry as anengineering tool or as a teaching aid. Productivity and efficiency of design is inherent with the useof the structured templates, especially when member selection or member verification is desiredfor structures that are composed of hundreds to thousands of elements. SEITRON also providesgreater comprehension as to the application and rationale of the seismic provisions with respect toductility design through its electronic referencing system.iiiSEITRON can play an important role for the education of students as well as practicing engineerswho would like to become familiar with the new seismic code. It can provide a practical tool forelemental design.ivTable of ContentsTitle PageAbstract^ iiTable of ContentsList of Figures^ viiiList of Tables xiiiAcknowledgments^ xvCHAPTER 1INTRODUCTION TO AN ELECTRONIC DESIGN HANDBOOKA. Introduction^1B. Purpose and Justification^3CHAPTER 2A CONCEPT FOR AN ELECTRONIC DESIGN HANDBOOK: THE HYPERTEXTSYSTEMA. Definition^ 6B. Historical Highlights^ 8C. Advantages of Hypertext 10D. Disadvantages of Hypertext^ 14E. Applications of Hypertext 17F. Anatomy an Expert System^ 18i. Inference Engine 20ii. User Interface^ 20iii. Knowledgebase 22a. Knowledge Acquisition^ 24b. Knowledgebase versus Database^ 27CHAPTER 3OPERATIONSA. Components of SEITRON^30B. Clause 27 Knowledge Base^ 32i. Level 1^ 35a. Table of Contents 37b. Index of Topics^ 38c. Map Organization 39ii. Level 2 and 3^ 40iii. Example of Clause 27 Knowledgebase^ 41C. Ductility and Redundancy Requirements 50i. Ductile Moment Frame^ 53ii. Nominally Ductile Moment Frame^ 55iii. Ductile Braced Frame 57iv. Nominally Ductile Braced Frame 60v. R-Factor^ 62vi. Ductility Requirements63D. Spreadsheet Design Templatesi. General^ 65ii. Formatted Spreadsheets^ 66iii. Structured Spreadsheets 67iv. Batch Mode^ 70v. Spreadsheet Advantages^ 71viE. Template Design Componenti. General^ 72ii. Interface and Communication^ 74iii. Overview of Template Design Modules^ 76iv. Features of Design Templates^ 79v. Modification of Templates 80F. Design Template Example^80i. Column Example 83CHAPTER 4SUPPORTING INFRASTRUCTUREA. Cursor Appearance^ 94B. Types of Buttons97C. Menu Line^ 100D. Use of Help System^ 102E. Knowledgebase Button104F. Information Library^ 105G. Shape Library 110CHAPTER 5CONCLUSIONS^ 115BIBLIOGRAPHY^ 120BIOGRAPHICAL INFORMATION^ 123viiList of FiguresFigure 1Hypertext System of Reference Manual^13Figure 2Hypertext System for Tutorial^13Figure 3Hypertext System of Brochure^ 13Figure 4Expert System Software Structure^ 19Figure 5Framework of Knowledge^ 26Figure 6SEITRON Title Page^ 30Figure 7SEITRON Main Index^ 31Figure 8Structure of Clause 27 Knowledgebase^ 33Figure 9Clause 27 Knowledgebase Relationship between Levels^35Figure 10Access to Clause 27 Knowledgebase via theTable of Contents or Index^ 36Figure 11Table of Contents^ 37Figure 12Index of Topics^ 38Figure 13Map Organization^ 39Figure 14SEITRON Title Page^ 41viiiFigure 15SEITRON Main Index^ 42Figure 16Access to Clause 27 Knowledgebase via theTable of Contents or Index^ 43Figure 17Table of Contents Revealing Ductile Braced Frames Topics^44Figure 18Investigation of Diagonal Bracing Memberswithin Ductile Braced Frames^ 45Figure 19Diagonal Bracing Members Code Specification toClause^ 46Figure 20Diagonal Bracing Member Commentary to Clause^47Figure 21References to Clause 27, Liu^ 48Figure 22Map of Seismic Clauses Illustrating Code Requirementsfor DBF's^ 49Figure 23Frame Ductility Requirements Title Page^ 51Figure 24Access to Frame Ductility Requirement via the Index of Topics^52Figure 25Frame Index^ 52Figure 26Ductile Moment Frame^ 53Figure 27Ductile Moment Frame with Beam as Critical Element andDesign Requirements for Beams^ 54ixFigure 28Nominally Ductile Moment Frame^ 55Figure 29Nominally Ductile Moment Frame with Panel Zone asCritical Element and Design Requirement for Panel Zone^56Figure 30Ductile Braced Frames^ 58Figure 31Ductile Braced Frames with Design Requirement forFactored Compressive Resistance^ 59Figure 32Nominally Ductile Braced Frames^ 60Figure 33Nominally Ductile Braced Frames with Design Requirementsfor Bracing Members^ 61Figure 34Effective Earthquake Base Shear Reduction Factor^ 62Figure 35Ductility and Redundancy^ 63Figure 36Frame Configuration and Component Design Force Comparison^64Figure 37Design Module Index^ 76Figure 38Element Design Modules^ 77Figure 39General Design Modules^ 77Figure 40Frame & Composite Design Modules^ 78xFigure 41Compressive Resistance of Column, Class C^ 85Figure 42Compressive Resistance of Column, Class C with Help Box^86Figure 43Results for the Compressive Resistance of theDesign Example Column showing the Deformed Shape^87Figure 44Activation of the W Shape Library for theCompressive Resistance of Column, Class C^ 88Figure 45W Shape Index^ 89Figure 46W250 Selection Index^ 90Figure 47W250x49 Member Geometric Properties^ 91Figure 48Definition of "kx" from the Info Book^ 92Figure 49Effective Length Factor Data from the Info Book^ 93Figure 50Menu Line for Clause 27 Knowledgebase^ 101Figure 51Menu Line for Ductility and Redundancy Design^ 101Figure 52Menu Line for Template Design^ 101Figure 53Bending Resistance of I-Sections with Help Box^ 103Figure 54Help Info Library Activated to Show Info on "(KL/r)x limit"^106xiFigure 55Cover Page of Seismic Info Book^107Figure 56Title Page of Seismic Info Book^107Figure 57Index of Variables from the Info Book^108Figure 58Beta Information from Info Book109Figure 59W Shape Title PageFigure 60Access to W Shapes via IndexFigure 61Shape Table SelectionFigure 62W Shape IndexFigure 63W250 Selection IndexFigure 64W250x49 Geometric PropertiesFigure 65Good-bye!x iiList of TablesTable 1Principles of User Interface Design^ 21Table 2Nodal Relationships^23Table 3Navigation of Nodes^24Table 4Knowledgebase versus Database^ 28Table 5Template Features^79Table 6Column Design Example^ 87Table 7Cursor Appearance^ 95Table 8Button Appearance^ 97Table 9Description of Menu Line Button^ 101Acknowledgments"It is better to know some of the questions than all of the answers."James TurberJournalistThis thesis is dedicated to those people who have shown unfailing support in me over the years.Of especial thanks I give to the Natural Science and Engineering Research Council (NSERC),andthe Steel Structures Group of British Columbia for their scholarships which funded my research.With respect to industrial support, David Halliday of Coast Steel Fabricators is instrumental inproviding me with the practical aspects of engineering design.I am particularly grateful to Dr. Siegfried Fritz Stiemer, my graduate advisor, who saw potentialin me and encouraged my development.Eternal thanks and love to my parents, Christine and Joseph who believed "engineering is no placefor a woman" when I started my undergraduate work but have always been my most ardent fans.They will forever brag of my profession to friends and strangers alike.Finally, I would also like to thank Vincent Latendresse for providing computer support withSEITRON and for putting up with my seemingly endless and inane questions on why the programdoes not do what I programmed it to do.xivCHAPTER 1INTRODUCTION TO SEITRONA. INTRODUCTIONThe mass production of silicone chip technology has created inexpensive computing power.These hardware advancements have created a vast and diverse industry of software development.The computer is no longer limited to scientists and business personnel as analysis tool but hasreached a level of everyday dependency. This dependency may be witnessed in all facets of NorthAmerican life from the elimination of commuting to work while using the home office withmodem and fax communication to the use of computers to sign books out of the library.This information explosion is benefiting the user through the presentation of information via aplethora of graphics, video clips, animation, music, audio - multi-media. The user is no longerrestricted to a dull monochromatic screen containing rows and columns of data. Psychologistsagree that the use of graphics, colors, sound, video, enhance the perception of information andincrease its retention value.With the availability of the personal computer, PC, and its powerful computational andinformation management advantages, it is no wonder, that the PC has traded places with the"traditional" engineering tool of the slide rule. It may even ambitiously replace engineering designtextbooks.Within the structural engineering community, the greatest use of the PC is for structural analysis.The multitude of commercial software created for the structural engineer allows the designer toeasily specify the degree of high order analysis required when given an array of boundaryconditions and constraints. Software created for this purpose include those that perform staticand dynamic as well as finite element analysis on structures. The desired output may includeresultant stresses, forces, reactions and deflections.Very often, the role of the software is finished once the forces are determined; however, thedesign process is only partially complete. The engineer is left on his own to make use of theseforces by comparing these values with resistances of beams, columns, bracing and connectionsderived from the code guidelines.Another aspect of the design is in the sheer size of the structure which may be reflected in thelarge number of elements which must be sized. Depending on the dimension and complexity of astructure, the designing engineer may have to consider hundreds to thousands of elements withforces, displacements and rotations. For example, such a structure may be a telescope enclosure.During the design process, the actual computing time spent on analysis is minimal. However, dueto the large volume of variables and the sophisticated calculations required to meet code strengthand stability criteria, the iterative design of each element may take considerable time usingtraditional calculator and paper methods.Whereas the software market seems to be saturated with analysis programs, there are very fewpackages that design and check the appropriateness of the element with the structural designcode, whether that be the concrete or steel design handbook. A tool which combinescomputational skill with organization ability is beneficial to constrain the iterative memberselection cycle to hours and days instead of weeks and months.Further to the concept of a code oriented design tool, it would be beneficial to increase the toolkitrepertoire with electronic access to the structural design code. In SEITRON's case, the designcode is that of the CANS-S16.1. Advantages of an electronic code would be that code2requirements and theoretical background are linked such that the engineer may better comprehendthe rational of the design principles. Linked ideas should not be limited to text but mayencompass graphics, animation and other forms of multi-media.B. PURPOSE AND JUSTIFICATION OF SEITRONSEITRON attempts to address steel design needs within the academic and practicing engineeringcontext. The objective of this thesis is to expand the engineer's information network electronicallyand to expand the instruments in a design toolkit.SEITRON stands for SEIsmic elecTRONic Handbook and tries to emulate an electronic versionof a traditional steel design handbook. SEITRON helps to clarify the new Clause 27 SeismicProvisions as set out in the Handbook of Steel Design, CAN3-S16.1-M91 and provides designtemplates for member selection.Part of the motivation of this thesis is the fact that as seismic research progresses, the codes,which make use of these new findings, become progressively more complex and difficult tofollow. The Canadian steel code has become increasingly elaborate with the introduction of thenew Clause 27.The implementation of these provisions is meant to provide the necessary ductility andredundancy requirements for the basic types of steel frame construction. Prior to the 1989changes, it was reasoned within the industry that the inherent mechanical properties of steel andthe standard design practices provided adequate ductile frame behaviour. However, testsperformed in the 1970's and 80's have shown successful behaviour of some frames and lessdesirable characteristics in other. The purpose of Clause 27 is to quantify design practices such3that an adequate level of ductility and redundancy is reached for the principle types of steelframes.However, two factors limit its practical use: the inter-relativity of the clauses and the sometimeslimited theoretical seismic background of new practicing engineers.Part of the confusion of the new seismic provisions is in its inter-relational design requirements.Investigation of the clauses reveals a referral or a designation to other clauses, commentary orreferences. Although the objective of the linkages between clauses and other material is meant tointerpret or to avoid repetition of the constraints, the format of the clauses tends to confuse ratherthan to clarify.Furthermore, each structural component of each frame must be verified as a critical or non-criticalelement. Based on the condition of criticality, certain rules must be followed. Unfortunately, thecode is written in such a fashion that it allows for confusion of when to apply the clauses. That is,the conditional environment of "if A of frame X is critical then follow the design practices of Cfrom frame Y when C is critical" is evident.Also, sometimes the comprehension of practicing engineers with respect to seismic theory isrelatively basic. Therefore, an inexperienced engineer who combines the new design standardswith a basic understanding of the fundamentals is faced with elaborate and complex designpractices instead of simplified procedures.The objective of this thesis is to attempt to clarify and illustrate the design principles as stated inClause 27, CSA structural steel design standard, CAN3-S16.1-M89, that comprises part of theHSC Edition 91, and provide a practical instrument for design. This is done in three ways:41. Provide an electronic reference of Clause 27, along with electronic links tocommentary and references.2. Quantify the critical elements of each frame system and provide thecorresponding code design requirements through the use of graphics.3. Provide design templates as engineering design tools which utilize Clause 27other CAN3-S16.1-M91 design requirements.The approach taken in the design of SEITRON is to utilize the present state-of-the-art computertechnology in order to provide the qualifying relationship links that are inherent in the new code.SEITRON is operated through a WINDOWS environment of object manipulations and iconcommands which provide ease of use. Also, the utilization of graphics effectively illustrates theapplication of the code with respect to the basic frame type and particular frame elements ofbeams, columns, bracing or connection.In regards of the template design, the user has the option of working on individual elements orusing a batch mode process. During the latter, the computer automatically chooses members tooptimize according to strength and stability conditions.The development of SEITRON represents a promising start to improve and ease the steel designprocess. It can be used as an engineering tool as well as a teaching aid. It provides the possibilityof gaining greater comprehension of the application and rationale of the seismic provisions withrespect to ductility design. In the future, SEITRON may play in the future a role in the educationof students as well as practicing engineers who are unfamiliar with the seismic code.5CHAPTER 2A CONCEPT FOR AN ELECTRONIC DESIGN HANDBOOK: THE HYPERTEXTSYSTEMA. DEFINITIONHypertext is the term used to describe a system of associations of informational nodes withrelational links. The focus of this method is the control given to the user to explore a complexweb of, logically interlinked information according to his needs and interest. That is, the purposeof hypertext is to allow the user to choose his own course of reading and browsing with the aid ofan electronic information medium.This interaction between user and medium goes beyond that of conventional question/query orcomputer-user alternation of turns that is found in traditionally structured flowchart techniques.The progression of hypertext can be unpredictable and is dictated by the desires of the user.Traditional programming techniques follow a flowchart style of advancement where theprogrammer predefines the next course of action. However, in hypertext, there is no fixed routecomputed in advance and thus knowledge or information from a database is accessed "on themove". The defining feature of hypertext is the sensation of close involvement of the user whensuch interactivity is inherent.Information in a hypertext system is stored as nodes and the relationships that connect the nodesare termed links. Nodes containing purely textual information define the "text" part of"hypertext". However, information is not restricted to text but may contain other types of mediasuch as images, graphics, animation, video, and sound recordings. Thus the linkage of multipleforms of media is called hypermedia. The aspiration of hypertext and hypermedia is theelectronic transfer of knowledge from the computer to the user.6At present, hypertext is still in a state of technological infancy. Nonetheless, there has beenextensive development in the software and hardware technologies which advanced hypertexttechnology today. The growing success in hypertext comes with the use of the personalcomputer, (PC), for information management retrieval. In terms of hardware developments, thefalling cost of computing power coupled with the increased capacity in storage and optical disktechnology (or CD) have led the way to high quality graphics and imaging. Developments innetworking further fuel the information generation.Advances in hardware are not sufficient without the advancements in software. Both arecontinuing to allow for applications which strive to be user friendly. There are two main softwareadvances in PC technology which have made hypertext technology possible today: the graphicaluser interface (or GUI) and object-oriented programming (or OOP). [2][34]The graphical user interface makes use of graphical representations to perform tasks. As a result,these interfaces make computers easier to use through the manipulation of metaphors and icons.Graphical icons provide more powerful, flexible and direct representation of tasks and data thanprevious character-based systems.Object oriented programming allows a hypertext application to be divided up into discretemodules of objects. For example, within a hypertext application, there are objects consisting offields, buttons and graphics. Each module or object is coded with object specific characteristicsand functions. The program operates through manipulation of objects. Hypertext is createdthrough a composition of such objects. The advantage of OOP is that it reduces redundancy andrepetition of code from traditional programming.7A more detailed discussion of these advances as they apply to SEITRON is presented insuccessive chapters.B. HISTORICAL HIGHLIGHTSAlthough the concept of information retrieval via the process of organization and linkage is notnew, it has not been realized until recent technological developments occurred. In the 1940's oneof the pioneers of information management, Theodore Nelson, predicted that books would beobsolete by the year 1967. However, with software technology only recently having reached theability to manipulate some of these ideas, it will be a while before hypertext replaces books, ifever.One of the articles most cited as the birthplace of hypertext is Vannevar Bush's "As we may think"(Bush, 1945). Bush was appointed the first director of America's Office of Scientific Researchand Development by President Roosevelt in 1941. Even at this time, Bush was experiencing thebeginning of the information explosion and saw problems associated with the rapid growth ofinformation: [25]"There is a growing mountain of research. But there is increased evidence that weare being bogged down today as specialization extends. The investigator isstaggered by the findings and conclusions of thousands of other workers -conclusions which he cannot find time to grasp, much less to remember, as theyappear. Yet, specialization becomes increasingly necessary for progress, and theeffort to bridge between disciplines is correspondingly superficial."8With this plethora of information, Bush had a vision of a device which he called the memex,which like "an individual stores his books, records, and communications, and which is mechanizedso that it may be consulted with exceeding speed and flexibility". The Memex was to simulate thehuman brain in that is would use associative indexing, and not be a simple repository, "the basicidea of which is a provision whereby any item may be caused at will to be selected immediatelyand automatically after another". Hence the non-linearity of the system lends itself as an effectiveteaching medium. However, the microfilm technology of the time did not lend itself to the leveland complexity of indexing, retrieval and storage capacity required by the Memex.Although Bush defined the principles of hypertext, he did not name this field of endeavor. Theterm hypertext was created by Theodor Nelson in the late 1960's. Since that time, Nelson hastaken on the ambitious role of designing a network-based hypertext system capable of storing andproviding access to the world's complete stock of textual material, the Docuverse. Nelson hasdeveloped principles that will ensure that the system is capable of uniquely referencing, billions oftimes, textual material and their interrelationships and the copyright issues arising from their useand distribution. One key feature is that a piece of text is never written twice, in that eachdocument contains links to the original document rather than copies of its parts. Not surprisingly,the Docuverse is presently incomplete.One of the first serviceable computer facilities which utilized a hypertext environment wasinvented by Doug Engelbart. His H-LAN/T system, Human using Language, Artifacts andMethodology, was used as an environment to support collaborative work at Englebart'sAugmented Human Intellect Research Centre at Stanford Research Institute. The systemsupported documents, memos, notes, reports, planning, debugging and communication.Englebart's emphasis on the system was on augmenting or amplifying human intellect. As such hissystem was a support environment, in that the user was able to achieve more than would bepossible without it.9Since then, interest and activity in hypertext and hypermedia has grown steadily. Numerousresearch prototypes and commercial hypermedia systems have been developed. As awareness ofthis technology grows, there is a trend for the user to not go through the laborious routine ofprogramming his own interface but towards using commercially available interfaces such asHyperCard to create his own application.C. ADVANTAGES OF HYPERTEXTThe present use of hypertext is analogous to that of books. With hypertext as well as with books,the user is gaining information by browsing and reading. However, the difference between ahypertext system and that of a book is that the user traverses through the electronic system bychoosing the subjects that are of interest to him. He is not restricted, as with a book, to linearlyfollow information page by page but may jump from topic to topic as they are semanticallyrelated. Such a system with its high degree of user interactions and organizational aspects hasmuch potential in the freedom of accessing information. [25]The concept of an electronic encyclopedia with direct access between interrelated subjects definesa topic-oriented system. Furthermore, the value of a topic-oriented system is strongly related tothe completeness and variety of its information content. The greater the variety of form, style,media and point of view is, the greater is the potential for the user to explore, penetrate andunderstand a topic.10The advantages of hypertext systems are expressed in terms of♦ nonlinear organization,♦ modeling of associative thinking,♦ multiple information paths, and♦ linkage of large libraries.Nonlinear OrganizationFreedom in organizing documents is achieved. The writer/programmer may express the nonlinearaspects of a body of information through a web network. Each topic may be associated with asimilar topic with related links The organizational effect is that of a large database with nodes ofinformation connected with links which represent the relations among the nodes.The result is that one topic does not necessarily follow another as in a book format but hypertextallows the user to express non-linear aspects of information that are currently expressed by cross-references, side base articles, digressions, bibliography citations, and footnotes. Thus, in creatingthe hypertext system, the writer shapes the document or system to fit the information instead offorcing the information to an arbitrary structure. Similarly, the user may navigate through thesystem by accessing information that is pertinent to him.11Hypertext Models Associative thinkingA hypertext system is similar to the methods used by the human brain. Associative, non-sequential linkages are comparable to the semantic networks of human memory. Psychologistsclaim that the manner of thought in a human brain is pluralistic rather than sequential. Theundertakings of the mind explore multiple thoughts in a seemingly random manner instead of in adirected, sequential undertaking. That is, one thought may trigger another idea that may not betotally related to the initial thought in the conventional sense. By incorporating the parallel pathworkings of the human brain into the hypertext system, this suggests that information in hypertextform is easier to learn, understand and remember.More Paths to InformationThe same information may be organized in several different ways at once. Hypertext puts theorganizational flexibility and power of a document knowledgebase to use by stringing togethercommon modules of information to create many different types of documents. As a result, theuser may produce personalized documentation for audience-specific documentation. Forexample, a hypertext system may be navigated in such a way to produce a reference manual,traversed with other nodes to produce a brochure or directed with particular subjects to produce atutorial.12ChartFigure 1, Hypertext System ofReference ManualFigure 2, Hypertext System of Tutorialoio^'-1 PhotoText1.1- 1.1^1 Text;TableFigure 3, Hypertext System of Brochure13itt L.1 Fie fe UNICE ManualL1 ext -[Table I-ti:'211111fl,.i ^ttijTextxi Text^'TeL2jText!Photo(=LI[[L:icet 1.1lexLinkage of Large LibrariesHypertext allows users to link information comprising of knowledge bases and media types invarious ways while leaving the individual parts modified. Each node of information is a separateentity which the programmer may change or edit. The links are based on attributes of the nodes.The nodes and links are distinctive entities and exist independently of each other. In order for thesystem to operate, the attributes which the links are dependent on must be present in the node.Thus it is feasible to connect unlimited arrays of databases to the system.This seemingly simple concept of linkage of various media types was only recently accomplishedwith advances to software technology. Much of the difficulty in the linkage of text and graphicsoccurs due to the variation and incompatibility between interfaces. The challenge for softwareengineers is to create media integration interfaces and database linkage techniques which wouldprovide easy and powerful access to information of all media types.D. DISADVANTAGES OF HYPERTEXTThe practicality in a hypertext systems lies in its ability to:♦ handle a large amount and variety of information,♦ support many types of users with different skills and information needs,and♦ incorporate the vast quantity of existing information available in traditionallinear form.14However, the problems associated with such as system arise as the system expands in size. Theuse of a hypertext-style database of linking relevant information to each other poses three mainproblems:♦ Information may be difficult to find,♦ Users may become Lost in Hyperspace, and♦ Hypertexts can be tedious to create and maintain.Finding InformationAs the number of items in a hypertext grows, so does the number of potential connections. Therespective paths from a given item quickly exceed the optimal "seven plus or minus two"[4]choices to present to a user at a given time. The "seven plus or minus two" programming rulerestricts the paths available such that the user is constrained to follow a directed path.When too many choices are made available to the user, he is left with a dilemma or search sub-problem in which he must determine the optimal next choice. Consequently, as the number ofpaths increase, so does the complexity in organizing relationships and creating the ability to returnto a specific topic or locate a specific topic.Users traditionally rely on the programmer to determine the sequence of topics and to employconventional cues that signal relationships among topics. Such organizational cues may beinformation management classified by relative importance or by chronology. When anorganization network is not obvious, information becomes hidden and thus useless.Although the impression of non-sequentiality is apparent to the user, the writer/programmer mustfocus on information management of schemes or informational hierarchies to organize data. The15links between ideas must also be discrete and explicit in order to lead the user from one subject toanother and allow him to see the direction or progression of the link.Lost in HypertextHypertext systems may contain a variety of information management schemes. However, withinits various hierarchies and networks a clearly defined organization is required such that users maybe able to follow the rational of relationships. The combined effects of organization uncertaintywith the large number of topics or items creates disorientation problems for the user. Users mayget lost in the network. A rapid succession of jumps between items may appear confusing to theinexperienced user. Also, forcing users to backtrack adds to anxiety and confusion.A possible solution to getting lost is the use of graphics, such as a map in order to structureinformation. The representation of each item of information with respect to its context in a mapmay be a basis for user reorientation. However, the breadth of information that may berepresented in large knowledgebases can make such mapping schemes difficult to implement andmaintain. Such a system would need constant upgrading when links and nodes are added.Creation and Maintenance of HypertextThe author decides the coordination and relationships between information points. If obscurepaths are followed, it may be hard to locate the proper or any information. Likewise, if theauthor's associative powers are weak, meaningless links could be created and a worthless databasemight be generated. To ensure potentially successful use of the system, the programmer must beaware of the logic and organization behind the links and its impact on the user.16Also, since one of the advantages of hypertext lies in the use of large multi-media systems, theissue arises as to which author is given the task of pruning and editing the system. Thecomplication created by multiple authors create the additional responsibility of assigning a singleauthor or many to decide on the relevance and suitability of links. Needless to say, the systembecomes difficult to maintain.E. APPLICATIONS OF HYPERTEXTThe characteristics of hypertext and hypermedia make it well suited to applications involving ahigh degree of user interaction. While hypertext applications are presently used in computer-based training and education, its usage is rapidly expanding to cover such applications as:♦ entertainment,♦ electronic publishing,♦ on-line information systems,♦ computer-aided learning systems,♦ diagnostic and repair manuals,♦ group support systems, and♦ multimedia authoring systems.17F. ANATOMY OF AN EXPERT SYSTEMHypertext systems are part of the computer science which deals with artificial intelligence, (Al).The concept of AI is the development of computer-supported techniques which could emulatesome of the natural capacities of the human brain. Al encompasses many topics, from computerspeech recognition and vision to different levels of problem solving. The development of Alprograms which in some way imitate the behaviour of skilled human experts in problem solving iscalled expert systems. While expert systems are a sub-branch of AI, Hypertext is also part of thedomain of expert systems. [3] [17][22]While the scope of this thesis is not to cover the discussion of knowledge engineering designprinciples, a general overview of the basic concepts are useful for completeness.The philosophy of artificial intelligence programming is to extract practical knowledge that isgained by experience and exposure and organize it into rules such that when a problem ispresented, the system may replicate the problem-solving techniques of an expert and provide arational conclusion.The key characteristics of an expert system are♦ the system makes inferences and deductions from information providedto it,♦ knowledge is applied in order to solve the problem,♦ the problem is narrow and specifically defined,♦ the system is designed to cope with uncertainty,♦ the knowledge base is used to guide and constrain the search for asolution, and18earr.fw.elptlikkijSet of empirical ruinscomprising tacks arok nettristics................. ..................*Prti4gsefke*(111^............^.. . .. ...............^... .4*81*RaPsf4sft.k.gk4••••1°^a♦^the system questions the user while in a conventional program, the userinterrogates the machine.Although hypertext does not necessarily make use of rule-based logic and associated uncertaintyof rules that are inherent in artificial intelligence systems, its principles of the linkage ofknowledge adheres to the concept of information and knowledge transfer of expert systems.The basic components of an expert system consist of the user interface, the inference engine andthe knowledgebase. Figure 4 describes these components. [3]Figure 4, Expert System Software Structure19i. INFERENCE ENGINEThe inference engine is the protocol for which rules and data from a knowledgebase areprocessed. In conventional programs, its execution is dictated by the programmer who selects thesequence of operations. However, in an expert system, this predefined structure does not existand the progression of the program is open to the user's needs. The task of the inference engine isto select and apply the appropriate rules that the user requires as he progresses through thesystem.The inference engine is supposed to perform the following activities:♦ decide on data required to solve the problem,♦ obtain data,♦ use rules in knowledge base to draw inferences when used in an expertsystem or implements linkages in a hypertext system,♦ record conclusions in the data base.20ii. USER INTERFACEThe term user interface refers to the front-end environment which acquires and displays data andresults. Thus for an interactive computer system, the focus is placed on the screen layouts andinteraction scenarios. Generally, it is not sufficient to simply provide a menu of choices in whichto guide the user. [3][6][16]The principles of user-interface design determine both the amount of data transferred and thenumber of interactions between the computer system and the user's terminal in a manner to meettime and presentation guidelines.When the interface is not discrete in its hierarchical menus or organization, time is wasted throughnavigation of menus and submenus which may in turn dominate the total transaction time. Carefuldesign of the interface can reduce unnecessary waste of time. Also, the need for a clear, visualpresentation is inherent to display data and also to show the position of the user within thesystem.Some of the principles which must be incorporated into the design include [37]:Item Maxim1 Menu design for frequent actions Use direct selection (icons + mouse, functions keys,etc.) to fix frequent actions to special buttons orfunction keys rather than through layers of menus.2 Fix frequent actions and symbols early Assign most frequent actions and symbols to mousebuttons, to function keys, or to first-level menus.3 Fix cursor location to selected actions andsymbolspredefined centers of gravity for quickly matchingscreen regions to single symbols or actions.214 Reference information Display and retain information that is likely to bereferenced later. Do not cover results that are likelyto be needed again with transient information.5 Fix frequently used sequence of actions For frequently used sequences of actions,automatically execute at the next action in sequence,and provide an exit to handle unlikely actions.Avoid asking question.6 Fixing screens to programs Minimize the number of screens to accomplish useractions, and group screens and programs tominimize overhead.7 Defining screen contents Cluster data that is needed within a short period oftime in the same screen region; omit other data thatis unlikely to be needed at the same time, andstructure it hierarchically by likely frequency of use.8 Match device capabilities to software uses Use device intelligence, high resolution, color andwindowing to decrease the number of userinteractions and maximize perception of results.9 Match amount of data needed to theamount displayed or enteredUse default values to minimize user interactions.10 Focus on frequent user functions Minimize the number of screen interactions and theprocessing required to accomplish frequent end-to-end user tasks.11 Hierarchical results Limit processing to most likely needed results;provide more by requests.Table 1, Principles of User Interface Design22iii. KNOWLEDGEBASEA knowledgebase is the entity which contains all the data, facts, rules and constraints which mayprovide a solution to a problem.The knowledge within hypertext consists of information in the form of nodes and rules in therelation of links. To promote the purpose of hypertext as "browsable knowledge", the structureof the information and its navigational ideas are essential as there is a strong relationship betweenthe structure of nodes and the types of links that may be used and ultimately in the presentation ofmaterial to the user. [13]The concept of knowledgebase representation and acquisition fall in the domain of knowledgeengineering and involves the manipulation of nodes, links and navigational devices. Generally,the main features of these concepts are discussed below.A node consists of♦ Name,♦ Information Units,♦ Features,♦ Index terms, and♦ Organizing Information.23The assignment of relationships between nodes is not restricted to similar ideas but mayencompass other associations. [25]Types of Links Maxims ExampleContrast The meaning of one term contracts,opposes or contradict the other inclusion Terms whose denotative meaning are apart of a more broad Terms that overlap in relations Relations involving attribution. bark-dogPart-whole relations Inclusion that is pragmatic rather thannecessary.faculty-professorTable 2, Nodal RelationshipsThe navigational aspects between nodes may be through the various transitions shown in Table 3.Navigational Method Maximmoving by comparison Searches in an information retrieval system.moving by gateway or pathway Follows a predefined path to assist the user in findingparticular information.moving by menu selection The menu may refer to nodes directly or may refer toanother menu of choices.moving by question(direct values vs. inferred relationarguments)Retrieval of information is by direct question.moving by navigational link Uninterrupted movement to directed link.Table 3, Navigation of Nodes24a. KNOWLEDGEBASE ACQUISITIONKnowledge acquisition is the process of extracting and formalizing the knowledge of experts sothat it can be included in the expert system knowledgebase. Knowledge is in the form of facts,description of objects, as well as the identification of relationships and the explanation ofprocedures.The extraction of knowledge from a human specialist into the knowledgebase is a difficult processdue to the heuristical nature, or rule of thumb, of the decision making process of the expert.Whereas the expert has proven his ability of applying sequence, timing and the use ofcombinations to maximum effect in solving specialized problems, the decision making process isoften difficult to articulate and to replicate in terms of rules. Often, experts are not conscious oftheir decision-making processes or of the finely tuned heuriStics that they apply to differentproblems.The knowledge base acquisition method utilized for hypertext is a variation of the expert skillprocured in expert systems and may remove some of the heuristical problems that are associatedwith it. The knowledgebase may be gathered from a variety of sources, ranging from humanexperts, to books, manuals, videos, animation.The steps in this general knowledge engineering process include: [17][12][22][36]♦ Identify knowledge,♦ Elicit knowledge,♦ Structure knowledge,♦ Represent knowledge,♦ Use knowledge, and25at on Knowledge♦ Validate, refine and maintain knowledge.The inherent nature of hypertext as nodes of information linked together diminishes theconstraints of decision making rules. The "rules" of the knowledgebase come from the relationallinks between the nodes. Instead of translating the cognitive and heuristic rational of a humanexpert, logical relationships or links must be clearly defined. Such relationships are to ensure thatthe end user will be able to progress through the expert system by a system of rules or navigatethrough the hypertext through a series of links to arrive at a solution or knowledge.The organization of knowledge within a node follows a structured guideline similar to that ofnested frames. This is due to the strong relationship between the structure of nodes and the typesof links that may be used. Figure 5 shows the nesting of knowledge. [22]Figure 5, Framework of Knowledge26Content knowledge corresponds to the domain knowledge that serves as information resource forthe hypertext application. In terms of the general knowledge engineering process, contentknowledge will result from the identification and elicitation of knowledge. Organization ofcontent knowledge consists of selecting relevant material and constructing it into nodes.Structural knowledge refers to the links that connect the nodes that were identified in the contentknowledge. The task of structural knowledge engineering is the specification of links of varioustypes between nodes.Application knowledge drives the usage of the hypertext. That is, it correlates the nodes and linksdefined from the content and structural knowledge to provide a direction in the interaction.Hypertext knowledge is an elusive meta-knowledge that refers to the way the hypertext isstructured and the information it contains. This concept is analogous to a good reference librarianwho has the knowledge of how a library is organized and where things are. This concept isdifficult to capture in knowledge representation and may currently only exist in the minds ofskilled hypertext users.Finally, interface knowledge consists of general information of the composition of the interface, aswell as of the nodal information.27b. KNOWLEDGEBASE VERSUS DATA BASEThe knowledge-based systems, in which hypertext systems rely on, provide facilities beyond thedatabasing capabilities that we have become familiar with over the last thirty years. While theconcept of hypertext resembles that of database management systems (DBMSs) with theirrelational links, the difference is in the intended use of the information. Where a relationaldatabase may resemble a hypertext database, the database systems usually emphasize selectionagainst criteria and reporting rather than reading and browsing. Therefore, the efforts requiredto create and expand a hypertext knowledgebase with the intended purpose of perusing andlearning is markedly different from that of relational databases. [14]The difference in contents between a traditional database and that of a knowledgebase is distinct.The domain of a database consists entirely of facts and data. The domain within a knowledgebasecontains both the domain facts and the associated rules governing the facts. Hence theknowledgebase is a superposition of the database and its rule structure. Data is not knowledgeuntil it is applied.The primary distinction between databases and knowledgebases is the fact that databases have apredetermined structure. Knowledgebanks or knowledgebases consist of the meaning of objectsand the semantic relationships between objects. Knowledge is expressed by rules, facts andconstraints in the form of object-oriented links The paths by which facts are related in aknowledgebank are determined ad hoc, as needed to solve a particular problem. Thischaracterizes a heuristic search in contrast to a structured approach.The methodology of knowledgebanks, because of its rules, acquires a fourth dimension that isbeyond that already provided in classical computing by databasing / data communications / dataprocessing.28Knowledgebase DatabaseFacts and states Information elements subject to:Relations between information elementsDecision rules InputMethodologies UpdatingConsistency control RetrievalDynamic extendibilityPropagation actionsTable 4, Knowledgebase versus DatabaseFurthermore, database inquires imply quantitative references and precise queries. Knowledgebankqueries are vague in the sense that the user has only an idea of what is required and may thus havemany options of navigation. Thus queries to classical databases are crisp whereas queries inexpert systems are vague with fuzzy sets, partial answers and perhaps unknown information andqueries in hypertext systems are based on the logistics of the relational linkages.29CHAPTER 3OPERATIONSA. COMPONENTS OF SEITRONSEITRON, synonym for SEIsmic elecTRONic handbook, is an interactive, knowledgebaseddesign tool developed for the seismic design of multistorey steel construction. SEITRONincorporates the seismic provisions of Clause 27, as newly introduced in 1989, from the CAN3-S16.1-M89, with ductility parameters and template design modules in an interactive user interfacefor efficient and fast data retrieval.Figure 6, SEITRON Title Page30A:r50.1End Seismic Hypertext SessieeSaiPreviousClause 21 linewierigeheseThere are three main components of SEITRON♦ Clause 27 Knowledgebase,♦ Ductility and Redundancy Requirements, and♦ Design Template.Figure 7, SEITRON Main IndexThe Clause 27 Knowledgebase and the Ductility and Redundancy Requirements componentsacts as a hypertext which allows the user to access code information and theory of seismic steelframe design parameters. The Design Template component is a practical engineering design toolfor the member selection of structural steel elements.Complementing these components are sustaining knowledgebases such as the InformationLibrary, Figure Library and Shape Table that clarify and support information presented from themain components of SEITRON.31B. CLAUSE 27 KNOWLEDGEBASEThe SEITRON Knowledgebase is based on the 1989 edition of the Handbook of SteelConstruction, by the Canadian Institute of Steel Construction, with respect to the new seismicprovisions, Clause 27. [7]Prior to the 1989 revision, there was no code assistance in the design of steel elements withrespect to seismic considerations. The National Building Code of Canada (NBCC) in its 1990revision has modified the method of analysis of seismic loads acting on a structural system. Thefocal idea is to assign force modification factors, R, to various structural systems in relation totheir capacity to absorb energy by undergoing inelastic deformations.To be consistent with the R values assumed in the analysis, the Limit States Design of SteelStructures, CAN3-S16.1-M89, was modified to incorporate the R values into the seismic designof structures. This modication to the steel code embodied the ductility requirements into the fourclasses of frames. The result is the creation of a new clause, Clause 27, which attempts tostandardize ductility requirements into steel frame design. Listed below are the four classes ofsteel frames and their governing clause numbers.♦ 27.2 Ductile Moment Resisting Frames, DMF♦ 27.3 Moment-Resisting Frames with Nominal Dutility, NDMF♦ 27.4 Ductile Braced Frames, DBF♦ 27.5 Braced Frames with Nominal Ductility, NDBFClause 27 relates the ductility requirements of structural components to the required strengthparameters. Consequently, inspection of a clause may refer to other clauses and Appendiceswithin the Seismic Design Requirements. The increased complexity of Clause 27 with respect to32LevelDefinition of structural steel designclauses as set out by CAN3-S1.6.1-M89,Level :2C...ammentary to design clauses.Level 3R.eforencos to design clauses.the organization and to the cross referencing lead to the creation of an electronically referencedhandbook, SEITRON.The SEITRON Knowledgebase is an information network that exists in three levels of complexityand depth. The first level contains the individual clauses as stated directly from CAN3-S 16.1.The second level contains the commentary with a discussion pertaining to the clauses. The thirdlevel is part of the reference or bibliography where the source of the clause is reviewed along witha brief extract or description of the author's paper.Figure 8, Structure of Clause 27 Knowledgebase33Level 1 DEFINITION OF CLAUSESClause 27 and its sub-clauses are located at this level and is cross-referencedbetween clauses on this level to that of the Commentary and the Reference levels(Level 2 & Level 3, respectively).Level 2 COMMENTARYCommentary regarding Clause 27 as discussed in CAN3-S16.1 is part of Level 2.Specific points as related to the clause in question or to any bibliographicdevelopment have been cross-referenced. The user may access Level 1 or Level 3information while in Level 2.Level 3 REFERENCESLevel 3 contains bibliographic research and development of particular clauses asbackground material. Bibliography of Clause 27 is cross-referenced to thecorresponding clauses and to the commentary. A brief abstract has also beenincluded in the references.34Level I.^\\,Clause 27 )- ........(/' Level 2^'''\‘Commeaaryi. LEVEL 1, CLAUSESAccess to the knowledgebase is first through the clause level. When more information is required,linkage exists between the clause and its commentary or reference. Consequently, relationshipsalso exist between the commentary and the reference itself. Thus a trilateral cohesion existsbetween the three levels of information.Figure 9, Clause 27 Knowledgebase Relationship between LevelsInvestigation of the first level of SEITRON is to Clause 27 Knowledgebase. Organization isthreefold. Access to the clauses may be through the Table of Contents, Index, or Map.35Figure 10, Acces to Clause 27 Knowledgebase via the Table of Contents or Index36ttc(e tElo. ltle41 0tclimoitEff fr■Rle4ftolt,^r<44§-)...............a. TABLE OF CONTENTSFor users who are not familiar with the code, the Table of Contents will guide the user to theappropriate clause via the organization of frame systems. The division of Clause 27 is by framesystems and sub-organized by elemental ductility constraints. Elemental ductility constraints areapplied to beams, columns, bracing or connection. When the Table of Contents is accessed, thefour frame systems are listed. By clicking onto the desired frame, the sub-topics of elementsguides the user to the ductility requirement in question. Depending on the frame and the sub-topic, there may be further sub-classifications to further assist the user in finding the correctclause.Figure 11, Table of Contents37i .:11RoiS:J:f1futi.::7„7.....• 77.. -^"". • :,•'... : ,...- : ••:•.......,-.... •......... ,.^.-, ,••,ND.G9K. ,.• .. ..;1 ti0f441,7•Ai:011p qipAlc .pEfilti:■.rivo(Pilrii4F,N.:$ . ' .. .1 .27:1.- f:•'.f.i*i6,>ai.i.Ag ••• :,..^:: ....:?:ii ,,S2....86‘,:illOcilvi:91;71 . z..:' ..,. .-:.'::.P:1.2. .•"fieci4.,:ir.1,0!deil:k.l.s Cm.kiii.A.sie i',7 1•3:::.1.4c.. -Krial43.Auvi., q..ekii , ' • .••24;.4•• TINI,Loe:$4..iilot*tinsy:tom2?-1:4 •.itip-Clf,agiloll-P:".iiiiiiv,..:31.;(*i;rjorroefitpv?7,,,,t $.....Sier4.1:.,itiast.........••:•• •' • • ••••• ••• .. ./....: •• ::::7.2.1.• 9'ii,5510 -•••'.. , : - :: ..^; ........:•:- •.-- : ••• :^•^•• ::,^::.;2?.21.1. 14•Wii:.p•tili,...rii,taibri '.:.' : • .::.., : -•.-: . ' • . •^•,27 211 .. ki,laitc DeiprnitOiCoilfrorli..ri.,':::.:,17:2'.1.j....t:riti6a1r.:mir.ri•• :.......:.-.:-. . .,... ^.....,,:11,21 .. •?. CtilicilNlio.*1.0ai:inl&*......: : ..:..;.71.41.3-..6i.ek.01,6 -.:6,144;•eit: ':, . -; ' •:. :,.V..2ta Ei!..54160;lii::34:..i§0k-P.Zay ' ....?7:^. ..,.221- 1:1 .,$11,F1 ,^,, . ...,., seoJo ^tieli,-. 2 ..? 2 .POli',„'" . 41 r.Nrinp ,.1' ..... - ' •27:22:'1 ri2E' l'iute.' 1 =E.(i‘a. ni:. !.',iikim,..,..,.;.,f,...'..3 I .irotkoi :''?" . 7Eliitril4;0!izor...1.?-511:777.?' .' ' ^kr r.; litm::0711    ^.. .27.212,..,.0......t . ,..;;..^.^•^• - • -^'^'^•^• .^.^'•:. :. ....: .INIRICIPIEIFIqHPPIICILIMI , .. : • -., .^. ....^.^..; ''. .-.'.. '. I101PiGiflif.ifTlUIVINVIXIYIZI ,.:: , .b. INDEX OF TOPICSIndex of Topics reveals a listing of Clause 27 Knowledgebase in sequential order. Scrolling thelist accesses all clauses as stated by the CAN3-S16.1. Also listed with the clauses are thecommentary and references. Thus the Index of Topics shows all three levels of theknowledgebase.The user can select a clause by scrolling down the list and clicking onto the desired topic.Similarily, the user may point to a letter in the alphabet list that is located below the scroll screen.Pointing to a letter will advance the list to the topics that start with that letter. The user simplyclicks onto the topic in question to advance.Figure 12, Index of Topics38•seigttlibteP4s14qmorebtatuafr■s.^tftuos,A5TAatumraemzetivsl^r,›tk,Thm zl tio^IN31ifot134an3istRthant.t r4rAzt Jr■t. Pattst2m1fOtt#A0Mit. evr116,1471UWiiiim 11r4 Wv iF Ctotctik151tti t  iiid Dom***tolpittUirc4:'c. MAP ORGANIZATIONIt is essential that the user be aware of his position at any time during browsing or navigation inorder to prevent being lost. A Map of the clauses reveals the linkage within each frame system oftheir elemental ductility requirements.Clicking onto a frame system reveals the elemental components of the frames and a breakdown ofsub-topics within each element. The advantage of a Map is that the user is able to seeimmediately all the code requirements for each frame system at once. The user may thendetermine which clause is relevant for his purpose and directly access the clause by clicking ontothe topic from the Map.Figure 13, Map Organization39ii. LEVEL 2 AND LEVEL 3Once the clause has been accessed, the relationship between clause, commentary and referencemay be observed. While in the individual clause, linkages may be present to direct the user tocommon provisions in another clause or to further explain a concept through a commentary orreference link. Thus linkage may be between clauses, between clause and commentary, betweenclause and reference, or between commentary and reference.The linkage between other levels is presented on the screen as buttons. Throughout the pages,guides or buttons have been implemented to provide navigational assistance by suggesting relatedinformation. These buttons and context sensitive navigational aids are discussed in Chapter 4,Supporting Infrastructure.40iii. EXAMPLE OF CLAUSE 27 KNOWLEDGEBASEIn order to illustrate the access of the three levels of Clause 27 Knowledgebase and the use ofbuttons as navigational tools, an example will be presented to show the steps involved inSEITRON. The presentation of diagonal bracing members from the Ductile Braced Frameclassification will be investigated.Access into SEITRON will show the title page of Figure 14.Figure 14, SEITRON title page41End Seismic Hypertext SOROOP"Clicking onto this screen will automatically present the SEITRON Index screen. All the topicspresented here are in the form of buttons. By clicking onto any of the buttons, SEITRON directsthe user to information regarding the chosen component.Figure 15, SEITRON Main Menu42Once the Clause 27 Knowledgebase button is clicked, the user is presented with the choice ofinformation retrieval via the Table of Contents or through the Index. This example will focus onthe use of the Table of Content.Figure 16, Access to Clause 27 Knowledgebase via the Table of Contents or Index43oaii it4 Eg'S atl44:Clicking onto the Ductile Braced Frame presents a sub-menu of topics.Figure 17, Table of Contents revealing Ductile Braced Frames Topics44From this sub-menu, the Diagonal Bracing Members button presents another sub-menu ofchoices. The Diagonal Bracing Member button is further segregated into two topics. Againclicking onto the Diagonal Bracing Member reveals the actual code specifications.Figure 18, Investigation of Diagonal Bracing Members within Ductile Braced Frames451Bracing members shall have a slenderness ration, Lit less than 113110/IFy.Symmetrical sections shall have width-lhit*SWISS ratios for flanges no greaterthan OS percent of the limits for Class "I sections and for webs no greater thanI OD percent of the limit for Clans 'I sections. Legs of angles and flanges ofchannels shall have width-to-thickness ratios not greater than 115/Iry. Built-upbracing MOME3f3fS shell hove slenderness ratios of the indiViditI4 parts no greaterthen 05 time the Mender:111FM ratio nil the member as a whole.1R7.4.3.1 DIAGONAL BRACING MEMBERS COMMENTARY ! 27.42.1 Diagonal Bracing MembersDuctile Braced Frames. Diagonal Bracing[MONote the title bar at the top left corner of the screen which reminds the user of the subject materialthat is being reviewed. In this example, the title pertains to the class of frames called DuctileBraced Frames.Figure 19, Diagonal Bracing Members Code Specifications for Clause clause in question is a direct rendition of the clause found in CAN3-S16.1.Characteristics of the Clause 27 Knowledgebase screen include the main subject title with theassociated clause number on the top left corner. Directly below the main title is the secondarytitle that references the frame classification. Information is presented directly below the titles inan information rectangle. The menu bar always appears on the bottom of the screen.Within the information rectangle, there may be buttons which allow the user to navigate to otherlevels of the knowledgebase. The linkage to the Level 2 Commentary may be seen with thebutton, Diagonal Bracing Member Commentary. This linkage is evident to the user by46The slenderness ratio is restricted because the energy absorbed by plasticbending of the balms diminishes WW 1 increased slenderness. Because et high4.1lifinfterrn; in TS. Member undergoing overall buckling. local budding is isexAcerbated.. with concomitant less in energy absorbing capacity. To controllocal buckling, the Irrnih Csr: width-thickness ltrrititi ere route severe than ClassI limits. Filling tubes with conmete ^L^. 27,  L^orproviding stiffeners are examples of inhibiting local buckling in criticalregions. built-up members may deteriorate rapidly under cyclic loading andtherefore the spacing of stitch fasteners is frrirrrided. Diagonal Bracing Members CommentaryDuctile Braced Frames, Diagonal BracingEticigazompt^flackthe change of appearance of the mouse cursor into a small window when he passes the mousecursor over it. Clicking onto this button directs the user to another information screen.Figure 20, Diagonal Bracing Members Commentary for Clause main title reflects the subject and the level within the knowledgebase. In this case, we haveaccessed Level 2, Commentary and as such, the main title shows this. The sub-title continues todisplay the frame system of which this information screen is a part.Access to other levels is again shown in the information rectangle in the form of buttons. Thebutton, Reference to Clause 27, Liu, allows entrance to Level 3 References. The function of thisbutton is apparent by its descriptive format. The first part of the button, Reference to Clause 27,refers to Level 3 References of the knowledgebase. The second part contains the name of theauthor/researcher who made the contribution to the clause. When more than one researcher wasinstrumental to the development of the clause, there are individual navigation buttons for each ofthe researchers such that the user has the option to investigate each author's contribution.47LIU, Z. and GOB_ S.C. I 91311. Cyclic load behaviour of coocreto-filled tubularbraces. ASCE Journal of Structural Engineering, 114(ST7), 1400-1G06.Cyclic load behavior of concrete-filled !octangular steel tubular bracingmembers is investigated. Nine full-scale specimen made from Alititi Grade 8cold-formed steel tubes were tested uncle: quasi-static cyclic ;roofing. Themain parameters of the study are:1) Presence of concrete2) urrerigth of curiclate3) effective slenderness ratio4) width-thirAness ratio.General cyclic behavior and modes of failure of the specimen are presented.Based on the observation of the behavior of test specimen, two procedureswe given to compute the first buckling load for such bracing members.=21 IC.ol) en% helotREFERENCES TO CLAUSE 27, UUIn the investigation of diagonal bracing members, the researcher, Dr. Liu, has provided much ofthe material that went into the formulation of this clause. Because of his contribution, the usermay access this information by clicking onto this button.Figure 21, References to Clause 27, LiuThe main title indicates the knowledge level that is currently being investigated and may be seento be of the same format as the References to Clause 27, Liu button that was previouslydiscussed. The secondary title is left empty as the paper may refer to more than one idea and thusmay affect more than one clause.The information rectangle within the reference level of the knowledgebase contains thebibliographic reference and a short extract of the abstract from the paper that is pertinent to thedevelopment of the clause.48tatArdtkafrli,^fli4tAtif i(W Moktake-3)o* '1fAKlitiffir4avooffie oA.Mattt.47;tlf ft 011.4 fiiit.Ott YAlk.046q.fAtmetaiigftt44it,^trukk4tOratih4 emir Wiwi40^(.0004attitillOitOtFinally, the progression of clauses and its hierarchical structure may be seen with the Map ofseismic clauses. This may be accessed through a series of steps that begin with clicking onto theContents button of any information screen. The Contents buttons navigates the user to the Tableof Contents screen. Finally, clicking onto the Map button that is located just above the menu linereveals the Map of Seismic Clauses. In this example, information regarding Ductile BracedFrames was desired so by clicking onto the DBF button, the complete clause layout is presented.Figure 22, Map of Seismic Clauses illustrating Code Requirements to DBF's49C. DUCTILITY AND REDUNDANCY DESIGNThe Ductility and Redundancy Design component of SEITRON is a graphical representationof the ductility and redundancy requirements of frames and how the code provisions areapplicable. [7] [8] [9] [37]Due to the complexity of Clause 27, it is often difficult for the user to apply and interpret thecode. While a system of linkages relates to the individuals clauses, it does not provide fullcomprehension of code application. An explanation of how and when to apply the elementalductility requirements was thus deemed necessary and a hypertext solution was the most worthy.This second component of SEITRON employs the use of colors and graphics to enhance itsexplanation of frame ductility. Within each frame, there is a possibility of its components (beam,column, panel joint, or bracing) undergoing large plastic deformations and which are identified ascritical elements. The ductility requirements are focused on the determination of critical elements.Some confusion exists in Clause 27 when it comes to determining which component is a criticalelement, and what constraints must be applied to both the critical element and to non-criticalelements in order to ensure ductility.Critical elements are assumed to undergo significant plastic deformation during an earthquakewhile "protecting" non-critical elements from begin overloaded. The latter are assumed to remainelastic.Depending on which element is critical, certain code provisions must be met to ensure ductility.Ductility and Redundancy Design is arranged such that the user determines the critical elementand SEITRON reveals which clause becomes relevant for all elements of the frame, and whether50it is critical or not. This component of SEITRON acts as an interpreter and teaching aid of howthe seismic provisions are to be applied.Figure 23, Frame and Ductility Requirements Title PageWhen the Ductility and Redundancy Design component of SEITRON is first accessed, theFrame Index is shown. The Frame Index pertains to the four basic types of frames used in thesteel industry and coincides with the code classification of the frames in Clause 27:♦ Ductile Moment Frame, DMF♦ Nominal Ductile Moment Frame, NDMF♦ Ductile Braced Frame, DBF and♦ Nominally Ductile Braced Frame, NDBF.For each frame system, a graphical representation of it main elemental components along with itscharacteristics and design parameters are shown. In additional to the frame systems, two topicsrelating to ductility and redundancy are also available.51'egarOSOMMOMMFINAWRNMOBrcling:MBMWMIMMaga•Previous • Back\g'ASV:iNominal, Ductile Moment Frames,witiation PactFigure 24, Access to Frame Ductility Requirements via the Index of TopicsFigure 25, Frame Index52Aleamsossewasaveseramstrommemosse Chencteristics: 4 0Joint composed ofBarn. Cokunn &Panel ZoneOne Or :numelements mayundergo plastificetionCritice: elementunorgoespiastificationDe i n Pattime ters(;) Cowes critical ElementE)80;t:ONANINSVOi. DUCTILE MOMENT FRAMESIn the case of Ductile Moment Frames, (DMF), the critical element is the element with thepotential to undergo large plastic deformations. The critical element could be either the beam,column or panel-zone. The force modification factor for DMFs is 4.0 which demands the highestductility requirements by reducing the seismic base shear.Figure 26, Ductile Moment FrameCritical components have the capacity to form plastic hinges in beam, and, where necessary, incolumn or in panel zones. The critical element must be proportioned and braced in order to beable to undergo large plastic deformation. The proportioning is done through the assignment ofClass 1 member sections such that redistribution of forces is possible. Non-critical elementsbehave elastically and are proportioned to be either Class 1 or 2 sections.When using the Ductility and Redundancy component of SEITRON, the user selects the criticalelement by clicking onto one of the Design Parameter buttons. Then by passing the cursor over53compossO ofNam,Pone: Ione61'1110F0eloroests.undergo p:astifiestemag.gigiihrgliletK;240 Column WNW ElementkiiiinftatiatakiNgCtiticai derrigiqundergoesplastiticationthe different elements comprising of the frame, the user notices the change in cursor appearance.This indicates further information may be revealed by clicking onto the various elements.Clicking onto the elements displays a rectangular information capsule which gives a briefdescription of the design requirements and an option to review the clause in detail. This option isrepresented as a rectangular button with the clause number. A direct linkage has been establishedwith the Clause 27 Knowledgebase for further explanations of the code requirements.Figure 27, Ductile Moment Frame with Beam as Critical Element and DesignRequirements for BeamsIn this example, beams are assumed to be the critical element. Clicking onto the individualelements will show an information capsule which summarizes the design requirements based onthe chosen design parameter. This system removes the confusion of when to apply which codecondition. Note the rectangular button highlighting Clause 27.2.2 that appears inside thepopped-up capsule which directs the user to the desired DMF clause from the Clause 27Knowledgebase.54,Zeti^\AtCharacteristics'=Limited amount ofinolarilic deformationthrough leouretaction, joint panelzcr:t rihearingconnoctiadolcrroations.ilttsimPaismeteu""*".. ...............MatakitiV: ." Matiao f9 Column Critical BementkiatiNOWARMii. NOMINALLY DUCTILE MOMENT FRAMEIn the case of Nominally Ductile Moment Frames, (NDMF's), there is limited amount ofinelastic deformation through flexural action, joint panel zone shearing or connectiondeformations. The critical element could be either the beam, column or panel-zone. The forcemodification factor for DMFs is 3.0 which demands the second highest ductility requirementsthrough the reduction of the seismic base shear.Figure 28, Nominally Ductile Moment FrameSimilar to the DMF, critical components have the limited capacity to form plastic hinges in beam,and where necessary in columns or in panel zones. The critical element must be proportioned andbraced to attain large plastic deformation. The proportioning is done through the assignment ofClass 1 or 2 sections to member sections such that limited redistribution of forces is possible.55Dttattl ParaftggagR = 3iirrsited amour3 ofinala Ott: aeformationthrough flexuralaction. join; panel 0 CUILIM Critieel Element*ffiNIMONNtatCharacteristics:Figure 29, Nominally Ductile Moment Frame with Panel Zone as Critical Elements and DesignRequirements for Panel ZoneThe format for information retrieval is similar to that of the DMF. The user selects the criticalelement by clicking onto one of the Design Parameter buttons. In this case, the panel zone ischosen as a critical element and the button is checked. Then by passing the cursor over thedifferent elements comprising of the frame, the user notices the change in cursor appearance.Clicking onto the elements shows a rectangular information capsule which gives a briefdescription of the design requirements and an option to review the clause in detail. From theexample bubble above, a direct linkage has been established with Clause 27.2.4 from the Clause27 Knowledgebase for further code clarification.56iii. DUCTILE BRACED FRAMESDuctile Braced Frames, (DBF's), follow stringent frame configurations and design criteria thatdo not exist for Nominally Ductile Braced Frames. These special configurations allow forredundancy in design and are shown on the Ductile Braced Frames screen. Also, braced framesdo not follow the critical element criteria found for moment frames. Their energy absorptioncapabilities are achieved by yielding of the brace(s) and correspond to a force reduction factor ofR = 3.0.One of the main concepts of the braced frame system is the assurance of force redistribution frombuckled or yielded braces. Because of this requirement, K, V or Chevron bracings are prohibitedin DBF systems. Limits have been placed on the slenderness ratio and on the width-thicknessratio to control local buckling. The factored compressive resistance has been reduced to take intoaccount the reduced load carrying capabilities under cyclic loading.Especially stringent are the connection requirements. A reduction factor of 1.5 has been assignedto connection ductility design. This factor corresponds to the minimum ductility requirements forsteel structures as specified in the NBCC90. This requirement is to ensure that the connectionwill always be stronger than the connecting elements and that the element will fail before theconnection. Due to these ductility criteria, the code has specific clauses to ensure♦ that the maximum compressive load to which the braced is subjectedduring initial cycles can be carried and♦ that the other connections sustain the nominal braced resistance forceand gravity loads57ECI=EIEone0 . f111Characteristics:R=3Illicflle brace4Crimea withcoin:mine bracinghalo the capacity toabsorb energythough yieidingbraces.Mini:man of 30%etoley View to becarved by 1 or Cnieces elnne*arz-N*2'fetee.ibretuffie ,.^ Crr.^Fir;4111.r.1/4„Crass Dratirie.043^L.7_11^ CIDFigure 30, Ductile Braced FramesWhen using the Ductility and Redundancy Component of SEITRON, information about eachframe component is revealed by selecting one of the design parameter buttons. An informationbubble appears to give a brief description of the design requirements. Each bubble contains therectangular button which directs the user to the corresponding Clause 27 Knowledgebase forfurther code clarification. Concurrently directing arrows point to the design parameter inquestion.If information regarding the Factored Compressive Resistance of the bracing is desired, the usersimply clicks onto the corresponding button. Once the button is selected, the circle is coloured.A characteristic of this type of button, called the radio button, is that the user does not have toclick on the circle to activate the button. Clicking on any of the text will activate the buttonproperties.58Net le bracildPine 3 withconoeniric bracinghawk dila capacity toabsorb enargythrough yieicling ofbraces.nyikin.Comp Tst/CroRe firecfre.ehlibirourn o'30%storey shear to becabled by T or Ch,ace a alonetaftitit-atiokKleOnce the parameter button is activated, an information bubble appears with the correspondingclause button which again links the user to Clause 27 Knowledgebase and arrows point to therelevant element of the frame system.Figure 31, Ductile Braced Frames with Design Requirements for Factored CompressiveResistance59Capacity of frames isitmitilti in its ability toabsorb OniugyPiroughbonding or a:dans:onref tombs'stereskon-anly 1 I ens-Ceinp 1^CorgeotiftCruse Brtiing Ciuss Bracing^"V"IireckwArAttt&P.Atkasiv. NOMINALLY DUCTILE BRACED FRAMESThe Nominally Ductile Braced Frames (NDBF) screen shows suitable frame configurations anddesign criteria. Nominally braced frames do not follow the critical element criteria found in themoment frames. Their energy absorption capabilities lie in the limited amount of energyabsorption through inelastic bending or extension of the braces which results in a force reductionfactor of R = 2.0. Of the four basic frame systems, NDBFs have the lowest reduction factor andthus the lowest ductility requirements.Figure 32, Nominally Ductile Braced FramesSince yielding is not inherent in NDBF, the criteria for frame systems is not as stringent as that forDBFs. Chevron, K, or V bracing are allowed. However, bracing members must conform toClass 2 section criteria to control local buckling.Connection requirements for the NDBF are also assigned a force reduction factor of R = 1.5.This factor corresponds to the minimum ductility requirements for steel structures as specified in60Ca•scAy frames isin its^toerNrgyN-sou•h insfresticben:tin or envisionof bracing niembsts.torseentat I.^ConrentikV"nirsting "" ""threcing  /•*MOMIVIVMthe NBCC90. This requirement is to ensure that the connection will always be stronger than theconnecting elements and that the element will fail before the connection. Due to these ductilitycriteria the bracing connection is designed for comparably high loads resulting from the low forcereduction factor of R = 1.5. Also, the specific clauses are directed towards the use of A and Vbracing to ensure that the beam can support the gravity load if the brace buckles.Figure 33, Nominally Ductile Braced Frames with Design Requirements for Bracing MemberAs with the DBF screen, information about each NDBF frame component is revealed by selectingone of the design parameter buttons. An information bubble appears to give a brief descriptionof the design requirements. Each bubble contains the rectangular button which directs the user tothe corresponding Clause 27 Knowledgebase for further code clarification, while arrows pointto the design parameter in question.In the example presented, the Bracing Members button was selected. The information bubblehas arrows pointing directly to the bracing elements on the system and the rectangular buttonhighlights access to Clause Componuntv. REDUCTION FACTORSIn addition to the frame ductility requirements, a summary table of reduction factors, (R factors),as it applies to each frame and to each component, is presented. Clicking onto any of themodification factors links the user directly to the clause and its supporting knowledgebase.The ductility of the frame is governed by the maximum R value of the frame. It is worthobserving that in the case of the braced frames, the R factor for the connection is lower than the Rfactor for the frame. This is due to the fact that the connection must always be stronger than theelement to ensure no sudden failure. The connection ductility requirement of R = 1.5 is the samerequirement if no ductility was applied and that the connection was to behave elastically.Figure 34, Effective Earthquake Base Shear Reduction Factors62FrameContiguretienDuctility Requirementst'VE"Lf0wo 20.Eft kgerotia totomortkIlwarr4R)54IF Azfdirvi 4 fin'fiNtrot:^,vi. DUCTILITY REQUIREMENTSA summary table of R factors for each frame along with a brief description of the frame's ductilityrequirements is shown. One accesses the Clause 27 Knowledgebase by clicking onto the Rheading or clicking onto one of the topics below the Code Requirements column. These links arehighlighted by rectangular buttons with rounded corners.For example, if the user is constructing a building using nominally ductile moment frames, he mayaccess the Ductility and Redundancy screen for the ideas regarding the main theoretical ductilityconstraints for design purposes. Looking at the table, NDMF s have a R factor of 3.0 which theuser must apply to reduce his base shear. Observing the ductility requirements for the NDMFconsists of inelastic bending and panel zone shearing, he would make special consideration in hisanalysis and design procedure so that this kind of energy absorption is utilized. Finally, whenspecific code constraints are required, he clicks onto the Clause 27.3 button to access CAN3-S16.1-M89 design specifications.Figure 35, Ductility and Redundancy63[Previous.. .Frame ConfigurationandComponent Design Force Comparisons(in terms of Seismic Base Shear)V,}1) BF'ket.1 .5(1 ,Nt =3.5N4 . 4.^ •F;)DE317 ND M F'^0FL3F^c.r-FLE_Deflection,When the R button is accessed, the Frame Configuration and Component Design ForceComparisons graph is shown. This diagram represents the seismic base shear force reduction asit applies to the four basic types of steels frame and are shown relative to each other.The use of graphs and diagrams is illustrative in presenting concepts. This diagram as well asothers are part of the Figure Library.Figure 36, Frame Configuration and Component Design Force Comparison64D. SPREADSHEET DESIGN COMPONENTi. GENERALIn as much that slide rules were a part of the engineer's tools during 1930-70's, so is that of thespreadsheet for the 1980's engineer. What the spreadsheet entails is the flexibility and ease ofcalculation in a "visual" environment. Spreadsheets ease the traditional problem solving techniqueof programming. The user is able to see the calculations and thus troubleshooting or "debugging"is relatively easy.Spreadsheets are adequate for data manipulation due to their inherent tabular form. However, touse this tool to its capacity involves the manipulation of range names for variable declaration andthe assertion of formulae in symbolic form, much like that of traditional programming. The majordiversion between these spreadsheets and traditional programming is in the presentation of inputs,calculations and output. The variables and formulae are always visual with spreadsheets, whereasin programming, they are hidden within the code. When coupled with the use of macros orprogrammed keystrokes for the operation of repetitious tasks or for the generation of menus, thespreadsheet may be more powerful than programming.The use of spreadsheets as a structural engineering design tool has seen a few changes. The firstgeneration method was coined formatted spreadsheet. Advances to multiple sheet technologyalong with GUI and WINDOWS technology have produced the second generation method whichis termed structured. Finally, the most recent generation is that of the batch mode where the useof databases coupled with the structured spreadsheet and macro programming may automaticallyand optimally choose and design member sizes.65ii. FORMATTED SPREADSHEETSOne advancement of the spreadsheet environment is through the use of formatted spreadsheets.Formatted spreadsheets make use of macro programming to create single keystroke macros toperform repetitious tasks. The formatted term arises from the use of regulated column widths tochange the computing environment to a working environment similar to that of traditional handcalculations and having the appearance much like that of an estimator's take-off sheet.The replication of the design process in electronic form follows the same steps as the solutionprocess in paper form. The engineer models the physical problem in a mathematical capacitythrough a succession of variables and formulae. These formulae would initially be written invariable form and numerical values attached later on. Using the regulated column widths of theformatted spreadsheet, the engineer uses each line as a variable or formulae declaration. Throughthe use of macros which incorporate the variable or formulae declaration into a single keystroke,the engineer may easily and quickly perform calculations.In terms of structural engineering, one of the most time consuming activities is in the codeverification of members. Standard hand and calculator operations would involve the calculationof the resistance of the member according to code specifications. This resistance value is checkedwith the applied loading and if the applied forces are greater than the resistance, a new member ischosen and its resistance is recalculated. This procedure would proceed until a suitable member ischosen to meet the applied forces and all the code constraints. More time and paper would beused in this repetitive process until all members of the structure are verified.The iterative procedure of checking calculated resistance with the applied forces is easilyperformed in the electronic case through the simple change of value of the variables. Through theuse of range names in the assignment of variables, a change in value of any variable will66automatically change the value of formulae which utilizes this variable. The result of thesevariable changes as they pertain to the output, or resistance, is immediate. In the case of thetraditional paper calculation, iterations means that each formula must be performed again, utilizingmore paper and more time. Thus the advantages to the formatted spreadsheet format is in theability for the user to visually see and check the calculations and to quickly perform iterations.iii. STRUCTURED SPREADSHEETWith the event of WINDOWS, the spreadsheet technology has advanced further in its increasedpotential of data manipulation and ease of use. The use of object manipulation and iconcommands greatly reduces the need for the user to remember keystrokes as was once the casewith traditional spreadsheets. The creation of multiple, stacked spreadsheets greatly enhances theconcept of a finite work space. Finally, the use of graphics, fonts, and appearance managereffectively displays the results of the data.In addition to the improvements in spreadsheets that were brought about with WINDOWStechnology, the power of the structured spreadsheet comes from the utilization of data tables toprovide auxiliary information. The manipulation of multiple files in conjunction with data basefiles allows three dimensional data analysis and processing which diverges into the realm ofknowledge base design.In the second generation of spreadsheet overlay development, multiple-sheet spreadsheetsincrease organization strength through the arrangement of information onto separate sheetsinstead of through the traditional staggered layout. Looking at i.e. LOTUS 123W spreadsheetapplication, a total of 256 separate sheets may be manipulated in a single file. As well, each sheetis the same size as the spreadsheets used in single sheet technology. In single spreadsheet67technology, blocks of distinct information or data must be arranged in a staggered manner suchthat when additions or deletions of columns or rows become necessary, other data is notunknowingly removed.The three-dimensional arrangement of data or information is analogous to the stacking of paper ina file folder. However, the three-dimensionality comes into play with the knowledge thatindividual sheets may be inter-related to other sheets within the file. Computation is not restrictedwithin each sheet but may encompass several sheets at a time. So instead of the singlespreadsheet's two dimensional characteristics of rows and columns, the structured spreadsheetattains the third dimension of depth with the stacking of sheets.An example of this arrangement may be such that calculations are on Sheet A, database on sheetB, data table on Sheet C, macros on sheet D and so on. The manipulation of calculations is notrestricted to a single sheet but may encompass several sheets. Such a calculation would be in theusage of data table values from Sheet C in the resistance calculations on Sheet A. The effect isworking with more that one file at one time and knowing where information is located.The development of formatted and structured spreadsheets, with respect to structural steeldesign, at the University of British Columbia has led to the creation of steel design templatesemploying steel shape table databases. For elemental design templates, member characteristicsmust be input into the calculations. Member characteristics may be obtained from the Handbookof Steel Construction, (HSC), shape tables or they may be calculated for specialized built-upsections. However, instead of manually inputting the values and manually changing these valueswhen new members are selected during iterative cycles, it becomes more efficient to createmacros and sub-menus to allow the engineer to select desired members and have the computerautomatically update the member properties from a data base.68Database files have been created for each of the structural shapes as listed in the HSC. Each lineof a shape file contains all the pertinent sectional properties for a particular size. Suchinformation includes the area, cross-sectional moment of inertia, section modulus, depth, width,thickness and other sectional properties. It is worth noting that all the information of a particularsize of member is entered as a single cell of data. This data string is later broken down todifferent components. The purpose of a single string character versus many strings is for the easeof data manipulation.When an element is chosen, the macro copies the database string to the shape table part of thetemplate. The string is then delineated into its sectional properties and transferred to the inputcells. When a new element is desired, the process is repeated.1. Choose element shape2. Macro combines database file of shape in question with template3. Choose element size4. Macro copies and delineates element string in shape table5. Sectional properties added to input cells.The entire process is fully automated and thus eliminates the user from manually finding thesection related parameter values in the HSC and manually typing the data. Another benefit of thissystem is that engineers do not have to "blindly" guestimate the choice of element. For commondesign purposes, a W-section database exists that orders elements by moment resistance. Thus bydesiring a certain moment, an "educated guess" selection of sectional size may be made.69iv. BATCH MODEThe design of multistorey structures can involve selecting and checking sizes of a large number ofelements. It can become very tedious to manually select and verify strength and stabilityconsiderations for each element. This is usually the case when the member forces in a buildinghave been determined in a structural analysis program. While many commercial softwarepackages are available for the finite, static or dynamic analysis of structures, a particular tool ismissing which adequately selects a member and verifies these elements according to the codeconditions.The Batch Mode Design involves the automatic computer selection or verification of members tomeet strength and stability criteria. The user provides a list of elements with their correspondinggeometrical properties, such as length, and applied forces. This information is usually the outputfrom a structural analysis program. Through the use of macros, the computer goes through a pre-selected member database against the applied forces and checks for its adequacy. If the memberin question is too small, the next larger size is checked. The process is repeated until all thestrength and stability conditions are met.Very often, however, especially in multistorey design, elements are not optimized for resistance.The wide range in forces and geometrical consideration of elements would result in a large varietyof member shapes and sizes if the optimization to strength and stability was the governing criteria.This requirement does not lend itself to economy, member availability, connection design, orpracticality. For such design conditions, a practical solution would entail the choice of a generaltype of shape and a solution would involve the user perusing through a condensed list of sizeswithin that shape. For example, in a multistory building one would want to standardize its columnsize by using only W250 shapes and as such a restricted database of all W250 sizes would beutilized.70This batch procedure can save many hours of tedious design work which becomes inherent inlarge elemental structures such as multistorey buildings, domes and telescope enclosures.v. SPREADSHEET ADVANTAGESOne of the major advantages of spreadsheet calculations is the ease of formulae changes. Unliketraditional programming where the formulation is hidden within the uncompiled code, thecalculations in a spreadsheet are transparent and may be easily modified. This ability is quiteimportant as revisions to the HSC and possibly some of the code design formulae are expectedevery four years. The interactivity of the spreadsheet eliminates the worry of input and outputfiles as modifications to variables are readily seen.The main advantages of using a spreadsheet environment for the design calculations are♦ layout of the calculations is similar to traditional hand calculations,♦ presentation of inputs, outputs, and calculations is clear, and♦ ease of formulation updates in the event of code changes.71E. DESIGN TEMPLATE COMPONENTi. GENERALThe rationale of the Design Template component was to create specialized templates forstructural design purposes which may be used repetitively, similar to a traditional computerprogram. These design templates usually encompass calculations where a steel element ischecked for strength and stability parameters against the constraints of the applied forces. Thesedesign parameters and member characteristics are dictated by the HSC.All the design templates are based on the latest code provisions of CAN3-S16.1-M89. In additionto its advantages as a design tool, the strength of the Design Template component lies in theability to access Clause 27 Knowledgebase for explanation of the design principles.The Design Template component of SEITRON utilizes the SEITRON interface as the input andoutput while a spreadsheet application in the background performs the calculations. The currentspreadsheet application used with SEITRON is LOTUS 123W. Templates have been created forvarious design purposes, such as beams, beam-columns and tension members, which SEITRONautomatically activates according to the design needs of the user. The user only sees the inputand output screen and does not concern himself with the calculations.The benefit of this system eliminates the need for the user to be familiar with spreadsheets while atthe same time the author takes advantage of the spreadsheet as a "visual" programming tool.Thus for each design screen, the user simply inputs the elemental characteristics and appliedforces and chooses the desired member size. By activating the CALC button at the menu line,SEITRON, through a system of dynamic data exchange and dynamic link libraries, transfers theinputs given by the user to the desired template and then transfers the output back to the interface.72(Dynamic data exchange and dynamic link libraries will be discussed later.) The user does nothave to concern himself with formulae as all calculations are performed out of the user's sight inthe background.However, the spreadsheet system linked with a user interface is even more beneficial to users withsome spreadsheet background. This is especially true for engineers who often request codemodifications. When certain clauses or formulae need to be modified, the spreadsheet may beeasily revised. This is due to the fact that the calculation module of SEITRON is independent ofthe interface. If traditional programming were to be used, the calculation programming codewould have to be modified and then recompiled. Moreover, if the programming code is part ofthe interface code then any code changes would be vulnerable to errors. The user would have tobe fluent in the programming language as well as in the architectural structure of the program. Onthe other hand, if formulae changes are needed but the user does not have the expertise to modifythe calculation module, the program might becomes useless and obsolete.The templates used in this component are a modification of the structured spreadsheetspreviously discussed. The difference between the structured spreadsheets and the designtemplates is in the capacity of the database. With structured spreadsheets, the database iscontained as a spreadsheet file for the ease of combining the database to the design templates.Such spreadsheets acts as stand alone programs that may be activated with macros.The shape database for use within the Design Template Component is currently organized in thesame configuration as SEITRON. That is, each member and its associated geometrical propertiesoccupy one page of the Shape Table Book.Although shape databases exist in spreadsheet files for macro activation within the spreadsheetmode, DLL technology has not advanced far enough to be able to activate macros while in the73SEITRON interface. Current technology dictates that a more efficient method of storage wouldbe to create external database files within an application program such as DBase®. Data transferand retrieval between the database, spreadsheet and interface would be through a system ofDDE's and DLL's much like that used for input/output retrieval between the spreadsheet andSEITRON interface.ii. INTERFACE AND COMMUNICATIONThe interface in the Design Template serves two purposes: a means of presenting engaging datawith the use of graphics and presentation managers and a coordination of the inputs and outputsrequired for the design. The advantage of the interface is in the ease of use. The user simplyinputs the elemental properties, applied forces and desired member, and SEITRON summarizesthe resistances with the calculations performed out of sight of the user.The SEITRON interface is based on WINDOWS® technology. To utilize the data transfercapabilities from this technology, the spreadsheet must also be a WINDOWS application.Applications such as LOTUS 123W®, EXCEL®, and QUATTRO PRO® are suitablespreadsheets. Communication files between each of these spreadsheets and with SEITRON areslightly different. Templates used within this thesis make use of LOTUS 123W spreadsheets.Communication between WINDOWS applications relies on Dynamic Data Exchange, (DDE).The DDE protocol defines a strict set of rules that allows an application to send commands to, orget information from another application. The use of the DDE allows the processing of severalsets of data from several applications which may be running simultaneously. In the DesignTemplate component, SEITRON and 123W are both running simultaneously, with the former inthe foreground and the latter in the background.74In conjunction with the DDE, dynamic link libraries, (DLL's) are also employed. DLL's areseparate files that contain functions which WINDOWS applications can use to share code andresources.All communication of input and output data between 123W and SEITRON are performedthrough DLL files. Creation of DLL files requires experience in WINDOWS programming. Acopy of a programming language such as Microsoft C or Pascal, along with an assembler isrequired to write the code. With respect to the Design Template component, control of theinputs is from the DLL file which transfers input values from SEITRON to 123W and thentransfers the output from 123W back to the interface.75Aw:iyo• wrFrame & Composite eSiff0 44M1U iii. OVERVIEW OF DESIGN TEMPLATE MODULESOrganization of the Design Template component is broken down into three main modules:♦ General Design,♦ Element Design, and♦ Frame and Composite Design.Figure 37, Design Modules Index76xx/iKAM 3:. )^60* lt,e4xEt#Mitrtt1)0Iipttn).rft17.7-,:7,•§.4:74:WW.amft727~1.Seetfert Beam-Cub: me— ,Teesile IISS Member^•Tensile Member.,611Law..514.CarAct)ihu01'0-10 r 111100Y 10tiro 411,,LItt tuottimg!famgiff.:MS: 11?4::5mfluenee DiagramLuari Digttibutirsnafr*Mf tfize 1b11,14144eiretrAmf [aMer rn fie liftectii to orvithR Ofa■PlssuatilW titintiVr4VM.14410^ftreesiElement Design are those template dealing with individual frame elements of columns, beams andbeam-columns.Figure 38, Element Design ModulesGeneral Design template cover such templates as conceptual, load and reliability design.Figure 39, General Design Modules77Bearing Connection P-Deity et One Storey.5.14V.M.V.IIIMMW-NANNAVA.WAJYArLI,• ma wawa roa wwww ram uwaw- mwo =->Fta itt Conn do tee Ntl Modules,,NrioAmar74,& imreAmftcma,r,44 08 ^t-404 rrimm^'Maur #.ituttk 1)os(RMMEW°:-.:MtsMgM 1.; .^•^ • 2Plate Glitial11#01All..AMOVAMMW,..4: V4*.VAMem.&,Ductile Braced kerne DesignFriction Connection P.Delre of Muli:Storey.eer=fleir 66 113PliilhE 1406 fitt6fnut16 046** er6rhj6t•of tho 411) 44411(e40,40_ OP :ANN* W."^• &}^etM.:Composite Benin DesignFrame and composite design templates deal with moment frame, braced frame, plate girderdesign, connection design, story drift, composite beam design requirements.Figure 40, Frame & Composite Design Modules78iv. FEATURES OF DESIGN TEMPLATESThe design templates utilizing the SEITRON interface are standard in their format. Eachtemplate may contain a graphical representation of the element and comprise of Input andSummary sections.Common to all templates are other features worth mentioning. These are briefly listed in tabularform and are discussed in more detail in later sections.Features PurposeFields cannot be overwritten inSummary SectionPrevent unnecessary inputsCursor Changes over certain fields Information may be revealed byclicking onto the fieldMenu Line at the bottom of thetemplateCommand buttons for navigation orcalculationCursor Changes within screen The difference in cursor appearanceindicates navigational links orvarious informational linksGraphical elemental changes at loadedand failed conditionGraphics effectively illustrates thestable and failed modes of a designTable 5, Template FeaturesAlso, throughout all design templates, there are various information support channels. As withtraditional design handbooks, additional information such as a glossary of terms, member shapetables, various data tables and the like may be found. With SEITRON, support comes in theform of supporting knowledge banks of the Info Library, Clause 27 Knowledgebase, ShapeTable and Figure Library.79v. MODIFICATION OF TEMPLATESThe SEITRON interface and the design templates are separate entities. The SEITRON interfaceneed not be modified as the user input and desired output sections will undoubtedly remainunchanged. However, the flexibility to modify the calculations without affecting the interface isessential in the success of SEITRON as a design tool. Since the SEITRON interface simplycreates a link between the interface environment and the spreadsheet, modification of thecalculations is fast and simple. This is done by accessing the spreadsheet through 123W,modifying the formulae and saving the file for future use.In traditional programming, the coding must be modified every time there are changes to theclauses. This results in repeated transformations, debugging and recompiling of the program.Also, the program code containing the calculations is usually nested within the code for theinterface. Thus when modifications are required of the calculations code, the code for theinterface becomes vulnerable to accidental changes.Proponents to traditional programming may argue in favour of increased calculation speed whentraditional programming is used versus the reliance of DLL's to transfer data with the use ofexternal spreadsheet applications. However, increased computing speed does not outweigh theadverse modification considerations of programming.80F. DESIGN TEMPLATE EXAMPLEThe purpose of the Design Templates component was an attempt to illustrate possible futureenhancements of structural design tools with the available software technology of the presenttime. This component was not created to provide a complete set of templates to cover all steeldesign situations.At the present state of computer technology and within the constraints of this thesis, thepracticality of the interface with the design templates is limited by the speed of data transfer andapplications communication and by the available memory of the computing system. There is atradeoff between multimedia enhancements and functionality of spreadsheets. Because of this,there may be some templates that are satisfactory without an interface and function better in thespreadsheet format. Nevertheless, future developments of multimedia may increase with advancesin software and hardware and in turn enhance the use of multimedia interfaces as design tools.The concept of an interface in front of a spreadsheet design tool has many advantages. With aninterface, the programmer may control or restrict access to the formulation of the calculations sothat users are not able to unknowingly or carelessly modify the formulae. In the case ofSEITRON, the design templates may be easily modified by experienced spreadsheet users,however, the use of an interface forces the user to think twice about any changes as they mayaffect the operation of the interface.Another benefit of an independent user interface is in the use of multimedia, pictures, graphics,and animation, which may more effectively illustrate the design concepts than pure numbers. Theinterface provides a user friendly environment that are often not found in analysis applications.Analysis programs often require the user to be fluent in the "application language". Through the81creation of a user friendly interface, the programmer may create an environment which is easy touse but at the save time retain the computational powers of the analysis program.A common misconception of the user friendliness of the interface may be that any layman maydesign structural entities. The argument is, only the experienced engineer would understand theconcepts and theory of the analysis and would be able to determine if the numerical results werereasonable or not. The interface allows the engineer to concentrate on the engineering and not toworry about correct syntax of the application.The selection of templates used in conjunction with the SEITRON interface was based on theideas of♦ functionality of the spreadsheet,♦ possible graphical or animation enhancements to further illustrate the concept,♦ usefulness and practicality of template,♦ speed of data transfer template, and♦ educational advantage.The design templates presented in SEITRON are for the elements most commonly encountered indesign and satisfy the conditions above. A current list of templates that are used with SEITRONinclude:♦ Column Design of I-Sections,♦ Column Design of HS S-Sections,♦ Tension Design of I-Sections,♦ Tension Design of HS S-Sections,♦ Beam Design of I-Sections,♦ Beam Design of HS S-S ections,♦ Beam-Column Design of I-Sections,82♦ Beam-Column Design of HS S-Sections,♦ Bearing Connection,♦ Friction Connection,♦ Shape Classification,♦ P-Delta Displacement, Single Storey,♦ P-Delta Displacement, Multi-Storey,♦ Bracing Design of HSS-Sections .This list is just a sample of the design possibilities with SEITRON and may be expanded at afuture date.While most templates may be enhanced with an interface, there may be some instances where it isnot desirable to do so. Such an instance would with the Batch mode templates. The Batch moderequires the arrangement of data in predefined columns and positions because operation of macrosis through the relative movement of cells. Using an interface necessitates the transfer of data froma structural analysis program to the interface and then further data transfer from the interface tothe spreadsheet. In the templates interfaced with SEITRON, the user inputs data directly to theinterface. The Batch mode adds an extra step which reduces time and efficiency and takes awaythe primary concept of the Batch mode as a fast and efficient tool.The column design template will be used as an example to illustrate the operation and show thebenefits of the SEITRON interface.83i. COLUMN EXAMPLEThe design of columns follows the code guidelines from Clause 13.3 of CANS-S16.1-M89. Steelcolumns are conveniently classified as short, intermediate, or long members and each category hasan associated characteristic type of behaviour. A short column can resist a load equal to the yieldload. A long column fails by elastic buckling and the maximum load depends only on the bendingstiffness and the length of the member. Most columns common to steel buildings are in theintermediate range and failure is characterized by inelastic buckling and is greatly influenced bythe magnitude and pattern of residual stresses and the magnitude and shape of the initialimperfections or out-of-straightness. The code constraints are to ensure stability and strength ofthe member.Because the resistance calculation of columns is complex and is dependent on many variables, asimplified table of compressive resistances does not exist. The column design template bridgesthis gap as a useful design tool.Characteristic of most design screens are an Input section, Summary section, graphics and menuline. The Input section contains all the variable inputs and is usually located at the top section ofthe screen. The Summary section contains purely results which is read-only information and islocated on the bottom section of the screen. The graphics is located to the left or top of thescreen and may change according to the results of the calculation. Finally, the menu line is alwayslocated on the bottom of the screen.84Membei MAC s 43 I--1tfj.),:p613:7REjWI* 1.weernon,vecovriredvmvbervennivon-.111111321U2514.91003.bit !MUD hAN rgtio CF‘ss of Member [ 13.12Esint$,Me Comp, Res:1248mm  L^.44ENBK .•••• ^StsbittL • : • •••••:.4ft., ELiiifi Plzvi^vir= att=2CAL{When the I-Section Column button is chosen from the Element Design Modules menu, thedesign screen as in Figure 41 appears.Figure 41, Compressive Resistance of Column, Class C TemplateThe Column Design I-Section template has all the typical screen characteristics discussed above,including a picture of a column. One unique characteristic of this design screen is that the graphicmay change with the results. During the input stage, the column is straight. However, dependingon the desired slenderness constraints or calculated resistance, the column may start to buckle anda picture of the undeformed column may be replaced with a deformed column.The menu line is the same for every template. However, investigation of the menu line revealsthat evermore important for a design screen is a Help button. For users that are unfamiliar withhow the design screen works, the Help button should always be accessed first. Other informationprovided from the Help button include hints about the layout or the format of the inputs andoutputs, or an outline of special features of the screen.85IOW the Eoatl and The tif3F44ttiriSlifX fir iitftleaded element by directly typing onto theiv-responding prawing the 'czar: button. the resistant...*" -----------Stebihty: Figure 42, Compressive Resistance of Column, Class C with the Help BoxDepending on the complexity of the clause which may influence the complexity of the designscreen, the Help Box may be very basic in its instructions or very complex. In this example, theHelp Box contains an information scroll bar which gives insight as to♦ how to input the member applied forces and characteristics,♦ how execution of the design screen works, and♦ how to get the definition of variables.Scrolling through the Help Box suggests to the user that data may be entered by typing directlyonto the corresponding field. Other information discussed include the execution of the designscreen by clicking onto the CALC button and the definition of variables. This is achieved bypassing the cursor over the field in question and noticing the change in cursor appearance to aquestion mark with a heavy arrow. Clicking onto the variable will then access its definition fromthe Info Library knowledgebase.A column design example using the following inputs will be shown:86ifffi thrte it ox-mmlea CALCChkse of Member f 2 t53^--1-^-r .. StrOiltith • 1 corm. itesistenca I 1$2.9 EKK I ^5:4232(y ...1 OK . 1Efficiewhdi^131 INPUT Value UnitMember Size W250x49Compression Force 1000 kNLength of column 5000 mmEffective length factor about X-Axis 1Effective length factor about Y-Axis 1slenderness limit about X-Axis 120slenderness limit about Y-Axis 200Yield strength of steel 300 MPaElastic Modulus of steel 200,000 MPaTable 6, Column Design ExampleThese values are typed over the corresponding cells. Once these inputs are entered, the CALCbutton is clicked to perform calculations. The output appears as shown. The advantages tomultimedia are shown in that given the inputs of the system, the column fails and the screen showsa deformed column.Figure 43, Results of Compressive Resistance of the Design Example Column, showing theDeformed Shape87dAttl irM30 trtlf)kCANADIAN IN331ITLITE OF !..ZTI.:ELCONS1ROC:1"1(iNand1.1:iiaa SS. Si:: 0:13f..)From the given applied loads and constraints, the column fails in strength with a compressiveresistance of 762.9 kN as compared to an applied load of 1000 kN. The slenderness ratios forboth X and Y axis are below the constraints so there is no problem with stability. The width tothickness ratios indicate a Class 2 designation for W250x49 which indicates the possibility of themember attaining full plastic moment but with limited rotation ability.One of the strengths of the template is in the ability of the user to choose pre-defined shapes thatare available from the HSC shape tables, instead of manually inputting the member characteristics.The button Member is clicked to give the user access to the Shape Table Library database.Figure 44, Activation of the W Shapes Library for the Compressive Resistance ofColumn, Class CThe Shape Table Library is presented as an overlay to the design template. Since the ColumnDesign, I-Section template was accessed, the Shape Table Library automatically accesses Ishapes (W shapes). More information regarding the Shape Table Library will be presented inChapter 4, Supporting Infrastructure.88W920W040W760W690W610W530W411l418W360W310MOW IndexOnce the W Shapes selection screen is accessed, the user chooses the nominal size of the member(Figure 45) and a more detailed section screen presents the member choices by weight breakdown(Figure 46).Figure 45, W Shapes Index89-$V.."..... 4 ,.....x-^.W250 Sections9f 250 x 167 ...^•.W250 x 1491Ir. ",,..44f0-:-N ^..W250 x 131,^s 4..)W250 x 115W250 x 101W250 x 09 AW250 x 00W250 x 73W250 x 67W250 x 58W250 x 49W2511 x 45 r.W250 x 39.kArIE di^'IVY 1:1milw.&ki........9-K-r..,„:1...„11"..F.:11 .„,:i „. ..04 1.1I''''' ..^7.-,21^1 ^.................._.,..Figure 46, W250 Selection IndexThe user selects the desired member size by clicking onto the member and then clicking onto theOK button. When a size of member is desired, the selection process is quick with the aid of themember selection windows. However, if there are further constraints to the member such as webor flange thickness considerations, it is beneficial to see these values. The button Member Infofrom the member selection by weight menu is clicked to see the geometrical values.90Dead load Cal kilko^At ea 626D rramA2To accept the chosen element as tho member for usein the design, click onto "VW: Click onto the "Back"bultonlo chose anuthei element.COQFigure 47, W250x49 Member Geometric PropertiesMember information for the W250x49 is shown in Figure 47. This menu is accessed by firstclicking onto the W250x49 selection from the list on Figure 46 and then clicking onto theMember Info button. If the member characteristics are not as desired, the selection process maybe repeated. That is, the user may choose the back button and go through the member selectionmenus again. If the geometrical constraints are adequate, the user confirms the selection byclicking onto the OK button. Control of the cursor goes back to the design template with thechosen material characteristics transferred to the template for use in the design.Another feature to the SEITRON interface is the ability of the template to present moreinformation than what is available on the screen. This ability is utilized in the Definition ofVariables that was mentioned in the Help button.91.Info.ialibutlax defines the effective length factor forcompression menobeis bent about the X-axis.Depending on the end condition of thecompression member. a variation of kxbetween 0.65 and 2.0 would apply to themajority of cases likely to be encountered inactual structures.f;^•[He Edit Text Page tieipflackPassing the cursor over the variables changes the cursor appearance from a white arrow to a solidblack arrow with a question mark. This change in appearance indicates a variable definition that isobtained through the Info Library database.Clicking onto the kx field reveals information about the field and also the possibility of moreinformation in the form of information buttons within the definition screen.Figure 48, Definition of "kx" from Info Book92Although the information in the definition screen may be presented in the form of a scroll field topresent more data, there may be some situations where there is not enough room to present all thematerial. In such situations, there may be additional buttons in the information bubble to accessmore information.Clicking onto the More info about kx button from the definition screen reveals common effectivelength factors as presented in the HSC for further clarification.if.., ,..^i^7^2114, . ^,Buckled shape ofcolumn is shown hy^■^' Idashed line ^1Ai.^;^*.,-7  ^7r r,...I r^ 4^Theoretical K value^0.6 0.7 1.0^1.0^2.0 2,I1 IRecommended design g,fifir, 0.6 I go IQ^.0 2.0value whets ideal condls^Iare approximated^ I"" .'^. i . 0404;4 ^,•:::„.:.:^  ' ;0AI^:^14ir^i ., :::• " i.::...:•^•^• •:...7::...; 01t41 . ^0 i^ii; .. '.''. . ''.^7 ... ..^..•: ......^...^, ..^• .. .... ..^a  -.3^,nr.,.. ^ ..... . . ... ,,. ..... .^.. .  kSta ^ RO-51adia!^.^" ...^..^.^.; . Figure 49, Effective Length Factor Data from Info Book93CHAPTER 4SUPPORTING INFRASTRUCTUREA. USE OF CURSOR APPEARANCEIntelligent design of user interface environments combines the ease of use with the ease ofinformation retrieval. The use of graphical linkages and the mouse pointing device provides theuser-to-interface interaction.Since all interactions are involved with the mouse pointing device, it is imperative that as muchinformation is available on screen at any one time for potential information retrieval. However,placing too many concepts of a certain idea all on one screen would clutter the screen and causemore chaos than the original idea of having all information at the user's fingertips.The solution of hypertext which effectively eliminates the clutter is by grouping pertinent data intonodes that may be retrieved through programmed links. The user is presented with buttons thatare able to access different concepts of the main idea.The next issue that arises is how does the user know when there is a link? That is, with so manygraphic entities all within a screen, how does the user know if a button exists and that he is notclicking onto a non-existent button and by doing so, he is clicking onto a dead end.In most cases, the presence of a button is obvious by its appearance. For example, buttons on themenu line are three dimensional in their appearance of a rectangle push button. Nevertheless,there may be instances where the shape of the button is not inherently obvious to indicate that alinkage exists.94Throughout SEITRON, provisions have be implemented in the interface to make the cursorappearance change whenever the cursor is positioned over an item that may reveal moreinformation.The normal appearance of the cursor is that of a small, pointer arrow. However, when the cursorpasses over certain field or buttons, its appearance will change to reveal that a link is in place orthat input is required. Below, in Table 7, is a list of cursor shapes, its meaning, and where theycan be found within SEITRON. These cursor appearance changes are limited to linkages that donot fall under the appearance of conventional buttons. The cursor stays at its default value of asmall, pointer arrow when conventional buttons are used. More information on conventionalbuttons are presented in the next section.CursorShapeCursorDescriptionMeaning Locationr4 default pointer throughout SEITRONU window Link to Clause 27Knowledgebase fromeither the clause,commentary, or referencethroughout SEITRON:1?Arrow withblack questionmarkInformation on elementalductility requirementsMoment Frameinvestigation within theDuctility andRedundancyComponent%,,,,Arrow withblack questionmarkDefinition of variablesLink to the Info LibraryDesign TemplateComponent1 I Shape Elemental data inputs Design TemplateComponentEHourglass Please wait Design TemplateComponent when theCalc button is activatedTable 7, Cursor Appearance95Within the Clause 27 Knowledgebase component, linkages are between clauses, commentary andreferences. The buttons are in the form of rectangles so when the cursor passes over thesebuttons, the shape of the cursor also changes to a box.While the user is in the Ductility and Redundancy component of SEITRON, a discussion of theductility requirements for each frame may be accessed. Within each graphical frame discussion,there are buttons relaying the specific design parameters and buttons in the menu line. Where it isobvious at locations where there are buttons, the user simply passes the regular pointer arrowcursor over the button and click onto the selection. Such is the case for the buttons within themenu line or for the radio buttons for the design parameter selection. However, there areinstances where the use of standard buttons may not be suitable for the application.In the investigation of elemental ductility requirements for moment frames, the user simply passesthe cursor over the frame picture and over the individual elements of beams, columns, panel zoneor connection to notice the change in cursor appearance. Again by pointing and clicking onto theelement, an elemental information bubble is unveiled. Within the information bubble, there isanother button providing access to Clause 27 Knowledgebase. This button is again not obviousso when the cursor is passed over the rectangle, the cursor changes into a window to indicate thepotential to navigate to more information.Within the Design Template component, a relationship has been set up between specific fieldsand the Info Library. This relationship defines variables used within the template design. Whenthe cursor is passed over certain variables of the template, the cursor changes to a black arrowwith the question mark to represent the possibility of variable definition. Clicking onto thevariable gives the user access to the corresponding definition screen of the Info Library.96Also in the Design Template component, when data inputs are required, the cursor changes tothe I shape to indicate to the user that data, usually numerical in format, may be entered.B. TYPES OF BUTTONSButtons have two purposes in the interface. They may represent a linkage or they may be used ina selection process. Their specific appearance governs their usage.The presentation of buttons is dependent on the type of information to be conveyed. Forexample, the shadowed buttons are used primarily in the menu line to direct the user to othercomponents of SEITRON, whereas the checkboxs in the Design Parameters section of theDesign Template component are used primarily for variable definition. Below, in Table 8, is a listof the types of buttons and their location within SEITRON.Appearance of Button Type ofButtonPurpose Location of UseRectangle Navigation Clause 27 KnowledgebaseDuctility and Redundancy Design• tittolin .^•Push Navigation throughout SEITRONMenu Lines^...^..^....^,^.^.^.• #11:0*. -..^s.^.:.:.;......^.., Rounded Navigation throughout SEITRON• 11 ;OW :..^. Shadowed Navigation throughout SEITRON_Wait.. : .(7) .BOiltiiii iRadio Button Navigationand SelectionDuctility and Redundancy DesignDesign Template Component97Checkbox Selection Design Template Component Table 8, Button AppearanceMost of the buttons listed above act purely as navigation tools (i.e., clicking onto them activatesthe link in a pre-defined relationship). There are two styles of buttons, the radio button and thecheckbox, that are often found grouped with other buttons of the similar style and whose functionis not purely navigational.The conveyance of a selection process in a graphical manner is usually presented in the form ofbuttons. Rather than providing an input box for the user to type in data, a selection of buttonswith the possible choices is usually provided. This choice of input provides three main advantages♦ minimize the number of user inputs and thus reduce the chance of human error,♦ ease of use, and♦ speed of input.As listed in the table, checkboxes and radio buttons are used in the selection process. Checkboxesare grouped by two's and are used primarily in the Design Template component in individualelemental design templates. Their function is to assign one of two values to variables that areused in the elemental calculations. That is, with a design criterion that has one of two possibleoptions, the checkbox buttons are employed such that the user may select one of the two choices.For example, in the Beam Design templates, the user must assign the type of curvature (single ordouble curvature) that the beam undergoes for each of its axis. Under the design criterion ofCurvature of the Beam, appears two checkboxes: one checkbox pertaining to single curvatureand the other checkbox pertaining to double curvature. The user simply clicks onto the checkbox98that is relevant to his design and the checkbox activates the corresponding variable for use in thespreadsheet calculations. Whenever a check box is selected, an X automatically appears.The use of radio buttons has a dual objective that is dependent on the location of its use. Theradio buttons are seen to be utilized in both navigation and variable assignment duties. In eitheruse, they are arranged together in groups of three or more.When in use as navigation tools, they form a sub-menu of navigational choices. Such an examplelies in the Index for the Ductility and Redundancy component. In this application, radio buttonsdisplay the types of frames that are presented. By selecting any of the radio push buttons, theuser is directed to the design requirements of the frame desired.Radio buttons are used for variable assignment in the Design Template component. The user ofradio buttons in variable declaration is similar to that of the checkboxes. However, where adesign parameter has more than two possible choices, radio buttons are used. Clicking onto thebutton colors the circle and assigns certain criteria in the design calculations.99C. MENU LINEInformation management is focal for SEITRON. While the format of an electronic handbookprovides completeness, easy navigation, and structured organization, it is easy for the programmerto expand such a system such that the realms of navigation are lost.As discussed before in the limitations of hypertext, the user may become lost when he is uncertainas to how he got there and how he is going to get out. In terms of the interface environment, theuser may progress to a certain component of the system through a series of linkages but thelinkage relationships may not be transparently clear or logical. The situation arises as to findingand utilizing suitable links such that the user may clearly navigate to the desired destination.SEITRON has been created with these problems in mind for maximum hypertext survival. Partof this solution is achieved by employing a standard menu line that is seen throughout all threecomponents of SEITRON. Within this menu line are buttons that are used in all levels andcomponents:Button Appearance Button Function^, 'r.. ^%k1A1^,.:::i :.:: ^t • Quit end SEITRONHelp activates Help menuMain Menu go to the Main Menu ofSEITRON"Sub-Menu" such asFrame Index or ModuleIndexgo to the Sub-Menu of currentcomponentnttita'ln.----$MOdtilo In ox'0 Know access to Clause 27KnowledgebaseI11:1 Backward arrow go to the page before the currentpageBack go to the previous page[1^Is,,,100Forward arrow go to the next pageCALC CALC calculates template with desiredinputs in the Design TemplatecomponentTable 9, Description of Menu Line ButtonsThe main button line maintains its position, shape and appearance throughout SEITRON suchthat the user may have easy access, familiarity and continuity for their use. Below are the menulines for each of the three components of SEITRON.Figure 50, Menu Line for Clause 27 Knowledgebase gin 6011 midiFigure 51, Menu Line for Ductility and Redundancy DesignFigure 52, Menu Line for Template DesignWithin the three different menu lines, there are buttons that are common to each component:Quit, Help, Main Menu, backward, Back and forward. These buttons ensure that users do notget lost. Through the use of the Main Menu, Sub-Menu, backward, Back and forward buttons,101the user has the option of going back to his initial starting point or to his previous screenwhenever he desires. It is in this way to ensure that the user does not move further intohyperspace to later discover that it is difficult to return to his starting point.There are also other menu line buttons for button functions that are component specific. In thecase of the Design Template component, the CALC button is included such that elemental designcalculations may be implemented.D. USE OF HELP SYSTEMThroughout each interactive screen, a Help button exists in answering common user inquiries.Once the Help button is activated, a Help screen appears. Each Help button is screen specific.Since each screen is unique in its contents and in the information that it is conveying, there arepoints of interest that may be relevant to one screen and may not be relevant to another.The Help button is more important in the Design Template than the other components. In theClause 27 Knowledgebase and Ductility Design components, the Help button mainly acts as ageneral overview as to the operation of the screen in question. However, in the DesignTemplate, Help informs the user of specific design criteria that is essential in the operation of thetemplate. For example, Help may♦ alert the user to special functions,♦ discuss how data is to be input,♦ discuss the sign convention of the inputs• review limitations to the design,102"Mk Ts-wz.„1881;exassammasamsam;Ltgelte2=21,^POti El foto rg NW*^hetilliglt; [InpuctMember 1 W259 N E0Ifttel/eat untrarssd lengitt,Im 3927.. :env. S:itemailtIrdin adienStew"ea= ■LOIMISELENSMALitalectetkillatInput the turves and the oharatstetiothz of thehonied element by typing di:et:fly onto thecorresponding input beans.Ail forces are tottered as absolute values.'rho direction dike end moments set:hewnin the diagrams ere drawn according w rEft. T^SKatuas0.9$1 OK11.41 VICKAKI:VV.1.431 :NG2.231; not♦ show how the supporting knowledgebase may be utilized, and♦ show how the supporting infobase may be utilized.As an example, the Help button from the beam template design screen will be investigated. Helpgives a general description of how to execute the template and it also alerts the user to specialthings to watch out for.Figure 53, Bending Resistance of I-Section with Help BoxIn this case Help presents four ideas as to the operation of the template:♦ Input of Forces and Characteristics,♦ Code Requirements,♦ Definition of Variables, and♦ Execution of Calculations.The Input of Forces is the most important concept to the template and is template specific. Thiscomment alerts the user to input all beam forces as positive values. Instead of inputting the forces103with their correct signage, the curvature of the beam that is expressed through the signage of theforces is instead explicitly entered as a button selection.The other comments from the Help screen are common to other templates. Code Requirementsinforms the user of the clauses used within the template. The Definition of Variables alerts theuser as to the use of Clause 27 Knowledgebase and Infobase to explain the variables used in thetemplate. Finally, the Execution of Calculations informs the user to click onto the CALC buttonto perform the calculations.While some of these comments are self-explanatory, other comments are useful in the successfulexecution of the template or screen. Thus the user is encouraged to read the Help button beforeattempting to execute the template or screen.E. KNOWLEDGEBASE BUTTONSince SEITRON can be used like an electronic handbook, access to clauses is one of the mostvital components of the system. The Ductility and Redundancy and Design Templatecomponents require the support of the clauses to inform the user of the code application. It istherefore vital to be able to access Clause 27 Knowledgebase at any time.The Know button that is found in the menu line is the linkage between the Design Templatecomponent to its seismic provisions. The Know linkage is to the Clause 27 Index, where clausesare listed in chronological ordering. The user may then scroll to the clause in question or accessthe Table of Contents button if the user is uncertain of the location of the clause.104F. INFORMATION LIBRARYThe Info Library is used primarily with the Design Template component. In these templates, thedata displayed in the Inputs and in the Summary sections are often written as variables. Theentire description of the input or output was not presented due to a limitation in the screen sizeand the system design requirement to show all inputs on one screen. Although care was taken toassign variables as representative as possible to the inputs and outputs, there may be uncertaintyregarding their meaning.A database of definitions that clarify the variables and gives some background in its use wasimplemented in the Info Library. While in the Design Template Module, the user may noticethat when he passes the cursor over certain input or output fields that the cursor appearancechanges to a large black arrow with a question mark. A link has been created with the field andthe Info Library. By clicking onto the field, SEITRON refers to the Info Library regarding thevariable at hand.For example, users may be familiar with the variable "lodx/rx" that is used frequently throughoutthe design templates. However, he may be unsure as to a suitable numerical value. Clicking ontothe kxlx/rx field reveals information regarding the slenderness ratio and a suitable value for use insteel design. All theory that is given as background material within the Info Library is based onthe code provisions of CAN/C SA-S 16 .1-M89 .105Hie Edit Text31^(AR inxt sage1 :(KIJOix limitRiogdasaag.; satin ia siefitittd^th4 3,0.02of dm RH:tot:an fortgth to she appituadoratings of gyration far et nanntregtiontv.,”1£ 41;4;10 th!! X *Ki.3.ins roaHanain sunder:: sms^a far anotopteRsian rnettatms 1130, oc stioniated eoC:AU1S115.1.114in^gc.“.4)W3l11:014, ^I!1^:vat::^?if, itrti^OK pogtt^.S.7:11 iiKaroo Kat MattS ttalifft Watt:Figure 54, Help Info Library Activated to show Information on the "(KL/r) limit"The Info Library may also be accessed on its own from the Main Menu. The title page andfollowing pages from this database are shown. Clicking onto the Next button of the Info Librarymenu line gives the user access to the Index of Variables. Note that the menu line is similar tothe menu lines of the SEITRON components in that control is in the form of Quit, Previous,Back Next buttons.106  1,^ bd.,'   ^He Edit Text Page HelpFigure 55, Cover Page of Seismic Info BookFigure 56, Title Page of Seismic Info Book107The Index of Variables is similar to the Index of Clause 27 Knowledgebase. An index of thevariables in alphabetical listing is presented. The user simply scrolls through the list to find thedesired variable and then clicks onto the variable in question to access the variable informationscreen. Similarly, instead of scrolling down the list, the user may click onto a letter of thealphabet that initializes the variable and the list advances to that variable.The variable Beta from the Bearing Connection design template is chosen as an example toillustrate the definition information screen. riVAr444^Wilf?". .^.^.cit^•^ 4py,4)...4et^•^cagAi [He Edit Iext lage Help• .^.^•^• .^ .^.^.S  •^,.<4.^Z.Vs.),•• ••••••),-.e..,, ..L.4 5),[ neviouFigure 57, Index of Variables from the Info Book108afifilMt • 's"^1.-VN* VElie Edit Text Date ftelpBetaBeta is the interaction factor applied tohearing conned:I ens subjected to combinedshear and tension.0.69 f A325 bolts , shear plane through shank;Mtf.*Agtfig*:g:i**Ai*f*Ali: '* 0.56 for A490 bolts shear plane through shankv. A;Mr:IMF;CEMZEOMMEriniOKFigure 58, Beta Information from Info Book109Seismic W Shapes data base book. • • • •^••:  ''........^:....^,^.G. SHAPE LIBRARYThe Design Template component of SEITRON requires the support of the Shape Libraryknowledgebase to provide member characteristics. The Shape Library comprises of thestructural sections listed in the HSC with their dimensional and sectional characteristics.Access to the Shape Library may be through the Member Size button from the Design Templatecomponent or through the Main Menu.Operation of the Shape Library as it pertains to the Member Size button has been discussed inthe Column Design example. Generally, when the Member Size button is clicked, the ShapeLibrary database is activated and the user is presented with a selection of member sizes.Operation of Shape Library from the Main Menu allows user access to any of the members thatcomprise the database.Figure 59, W Shapes Title Page110Seismic W Shapes data base book4,4---710111111144.%.^e,e,•44.[^Shape Table SelectionfM•kt,1,,,V.V.V.V.W.WJANALV.V.SWA PreviousFigure 60, Access to W Shapes via the IndexFigure 61, Shape Table Selection111The Shape Table Selection index of the Shape Library lists the shapes available for use. Theseshapes range from W shapes to Angles. Generally, clicking onto the desired shape accesses a sub-group of the shape by size. Clicking onto the appropriate size may reveal another selectiongrouped by weight. Finally, at the end of the selection process, the user may inspect the membersection dimensions and geometric properties by clicking onto the Member Info button.W sections are the predominate shape used in structural design. Due to the large range in sizes,W shapes are sub-grouped by their depth. Clicking onto W-Shape as the desired structuralmember reveals a choice of section sizes ranging from W100 to W1000. Clicking onto thedesired section depth will access the final listing of members with common depth but varyingweights. The user may find the desired size for use in the template design by clicking the OKbutton on he may review the sectional properties of that shape by clicking onto the Member Infobutton....---- .,,-"9 .. . r;,77..!.7 - -. ::7i''-v,..t'z rf^ • y.aiW Shapes1.131111Ii1i W20W840Wili11W690^,W610 '.:'W5301/1/460W410W360W310W250W200W150 Mwile_ ....--^—CIrt.sq:?.:Thutf.A.$.......,),ver.. OK^Help. .>'''''')^Index^i4wFigure 62, W Shapes Index112.VVIWAS,iTo accept the chosen element iIS the member for use]in the design, click onto "OW". Click onto the Tack" I;button to chose another element. i••••wmairia04wymmt&^,^•^' .W250 SEIC8110SW250 n 167I W250 x 1491 W250 x 131W250 x 115I W250 x 101W250 x 89W250 x 80Vir/50 x 73-W250 It 67• W250 x 58-W/511itW250 x 45vir25u x 39ute-scel Ent:5111,1 OK i Help 1 index ...C5ALSia, )vaiii:fe.w“elawa.a....3“, w nre.a.f.:vo4taFigure 63, W250 Sections IndexFigure 64, W250x49 Geometrical Properties113It is worth noting that at any time within the section process, the user may change his mind of thechoice of section by going back to the previous screen or going back to the Shape TableSelection index. Thus if the user is reviewing the sectional characteristics of W shapes and findsthat the properties are inappropriate, he may access another member with different depth byclicking onto the Back button or he may decide to use another shape altogether by clicking theShape Index button.Once the desired shape has been chosen by confirming with the OK button, all the sectionalproperties are transferred to the Design Template for use in the calculations.114CHAPTER 5CONCLUSIONThis thesis has attempted to explain the potential of a hypertext system as an integrated designtool. During the research and development of this system, the current steel design practices usingtraditional programming, along with the new seismic provisions and the design needs of thestructural engineering community were evaluated. Complex code requirements and the potentialof high level computing fueled the investigation of a new design tool. The outcome was acompilation of requirements which this thesis has endeavored to incorporate into the nextgeneration of graphical design tools:♦ provide a tool which may perform structural design and provide access to coderequirements,♦ clarify the design requirements within the steel code with the use of supportingmaterial in the form of commentary, references, graphics,♦ provide design tools for commonly used structural elements, and♦ provide user-friendly atmosphere.The advancement of seismic research has created new provisions to ensure ductile behaviour ofstructures. With these new provisions, Clause 27 of CAN/CSA-S16.1-M89, the steel designcode has recently undergone code changes to ensure ductile frame behaviour whereas in the past,ductility was deemed to be an inherent quality of steel design. Such changes have made the codedifficult to interpret and may have brought about confusion to the steel designer and fabricator.115In an attempt to clarify the seismic provisions, innovative computer solutions were investigated.The introduction of computer technology into the office environment provided an opportunity tointroduce new concepts and approaches into the design field.The choice of a hypertext system approach was considered to meet the challenges of these criteriathrough an interactive system based on linkages, Dynamic Link Libraries (DLL) and DynamicData Exchange (DDE) communication and supporting features of graphics, colors, buttons.Through a linkage system, a large knowledgebase of various media may be presented to betterexplain the code concepts. In addition, hypertext may communicate with other applications andas such, it may integrate other applications in order to meet its member design criteria.To answer the issues presented in this thesis, the interactive system SEITRON, SEIsmicElecTRONic Handbook, was created.SEITRON serves three purposes:1. Provide an electronic reference of Clause 27, along with electronic links tocommentary and references.2. Quantify the critical elements of each frame system and provide the correspondingcode design requirements through the use of graphics.3.^Provide design templates as engineering design tools which utilize Clause 27 andother CAN/CSA-S16.1-M89 design requirements.116To effectively fulfill these three purposes, SEITRON is organized into three main components:• Clause 27 Knowledgebase,♦ Ductility and Redundancy Requirements, and♦ Design Template.Part of the potential confusion in Clause 27 is the inter-relatedness of the individual clauses. TheClause 27 Knowledgebase component acts as a hypertext which allows the user to access codeinformation and theory of seismic steel frame design parameters. This inter-relationship iseffectively managed in an environment of links and buttons. Further, the use of graphics and theinteractive mode allows the user to access information that is pertinent to one's requirements andto omit nonessential material. The non-structured characteristic of SEITRON allows the userto browse through related material which in turn may clarify the seismic concepts.Such a browsing ability is inherent in the Ductility and Redundancy component which clarifiesthe inter-relatedness and overlapping of code conditions for the four main frame configurations:Ductile Moment Frame, Nominally Ductile Moment Frame, Braced Frame, and Nominally DuctileBraced Frame. This component is a graphical representation of the ductility and redundancyrequirements of frames and how the code provisions are applicable. The user chooses the criticaldesign parameter and SEITRON defines the code conditions for each of the frame elements withrespect to the chosen parameter.This component acts similar to a teaching tool with its graphics and pop-up information capsules.However, its function is enhanced with the power of linkages between the graphic capabilities andthe code provisions from the Clause 27 Knowledgebase component.117The hypertext ability of SEITRON is enhanced with the extension of spreadsheets as a usefuldesign tool. Presently, there are many software packages for the static, dynamic and finiteanalysis of structures but there are few tools available that are able to interpret the output fromthe analysis tools into useful members sizes. SEITRON addresses this issue with theincorporation of commonly used design templates with the hypertext system.In the Template Design component, SEITRON acts as an interface and controller of data flow.Inputs and outputs are presented in graphical fields for ease of design and presentation within theSEITRON interface. However, all calculations are performed on formatted templates behind theinterface. The user inputs the desired data into the corresponding fields and SEITRON transfersthe inputs and outputs between the template and interface. Communication between template andinterface is through a series of complex DLL's and DDE's.Convenience in the design tool is in the use of the steel member database for resistancecalculations and in the ease and flexibility of spreadsheet templates for calculation. In terms of themember database, the user no longer has to manually input sectional and geometrical propertiesfor design calculations but may choose the desired member through a menu system. The physicalSteel Design Handbook may be replaced with an electronic one.Strength in SEITRON comes with the recent WINDOWS® and Graphical User Interface (GUI)technology which allows communication between files and enhances graphics capabilities. This isimportant as the computing medium and the interface are kept as separate entities. Thecapabilities of SEITRON as a hypertext system are good, however, its computational powers arelimited and hence the formatted spreadsheets were incorporated to complete the computationalrequirements.118Further to the power of the spreadsheet is the ease of formulation changes that can be doneseparately from the interface code. Since design code changes are regulated every four years, thespreadsheet may be easily modified without becoming obsolete as would be the case in traditionalprogrammed interfaces.Finally, it is important that the hypertext system be easy to learn and use. Object-orientedtechniques were incorporated into the hypertext system shell to ensure that it is portable and userfriendly. The use of spreadsheets as the computing medium is also easy to learn and to modifywhen further code changes are required. Also, since SEITRON is not composed just of text butcontains a plethora of graphics, colors and buttons, the interactivity between user and system mayseem fun and may enhance reader perception of the material.It is the author's hope that SEITRON may serve not only as a design tool in a professional settingbut that it may also act as a teaching aid for engineers to acquaint themselves with seismic designprovisions.Figure 65, Good-bye!119BIBLIOGRAPHY1. ASCE, Expert Systems for Civil Engineers: Education, 1989.2. Asymetrix, Using Toolbook, A guide to Buildling and Working with Books, Asymetrix,1989.3. Beerel, Annabel C., Expert Systems: Strategic Implications and Applications, EllisHorwood Limited, England, 1987.4. Beaulieu, D., Perlynn, M., Dunbar, A., Adams, P.F., and Keller, D., The Effects of columnout-of-plumbs on the stability of core-braced buildings, Canadian Journal of CivilEngineering, 3(3), 1976.5. Birtwistle, Graham, Artificial Intelligence Graphics and Simulation, Society for ComputerSimulation, La Jolla, California, 1985.6. Blattner, M et al., Multimedia Interface Design, Addison,-Wesley, New York, 19927. Canadian Institute of Steel Construction, Handbook of Steel Construction, Fifth Edition,October 1991.8. Canadian Society for Civil Engineering, Earthquake Structural Design Seminar,Vancouver/Victoria, April 1990.9. Carpenter, James, Response of Steel Frames to Earthquakes, March 1990.10. Chien, Eddie, Connection Design & Ductility Requirements to NBC & S16.1, CanadianInstitute of Steel Construction, Willowdale, Ontario, 1992.11. Chien, Eddie, Low Rise Office Building Design Aid, Canadian Institute of SteelConstruction, Willowdale, Ontario, First Printing, May 1991.12. Cheong-Siat-Moy, Francois, Column Design in Gravity-Loaded Frames, Journal ofStructural Engineering, Vol. 117, No. 5, May, 1991.13. Chorafas, Dimitris N., Knowledge Engineering, Van Nostrand Reinhold, New York, 199014. Fleming, C. and von Halle B., Handbook of Relational Database Design, Addison-WesleyPublishing, Massachusetts, 1989.15. Hawkins, N.M. and Mitchell, D., Seismic Response of Composite Shear Connections.ASCE Journal of Structural Engineering, 110(9), 2120-2136, 1984.12016. LEA/AIE, Proceedings The Third International Conference on Industrial & EngineeringApplications of Artificial Intelligence & Expert Systems, Volume II, Charleston, SouthCarolina, 1990.17. Jackson, Peter, Introduction to Expert Systems, Second Edition, Addison-Wesley, GreatBritain, 1990.18. Jain, A. et al., Hysteretic Cycles of Axially Loaded Steel Members, Journal of the StructuralDivision, ASCE, Vol. 106, No. ST8, August, 1980.19. Krawinlder, H., and Popov, E., Seismic Behavior of Moment Connections and Joints,Journal of the Structural Division, ASCE, Vol. 108, No. ST2, February, 1982.20. Kennedy, D.J.L., Picard, A., and Beaulieu, D., New Canadian Provisions for the Design ofSteel Beam-Columns, Canadian Journal of Civil Engineering, 17(6), 1990.21. Lay, M., and Galambos, T., Bracing Requirements for Inelastic Steel Beams, Journal of theStructural Division, ASCE, Vol. 92, No. ST2, April, 1966.22. Liebowitz, J., and De Salvo D., Structuring Expert Systems, Domain, Design andDevelopment, Prentice-Hall, Inc, New Jersey, 1989.23. Liu, Z and Goel, S., Cyclic Load Behaviour of Concrete-Filled Tubular Braces, Journal ofStructural Engineering, Vol. 114, No. 7, July, 1988.24. Massey, C., Lateral Bracing Forces of Steel I-Beams, ASCE Engineering MechanicsDivision, 88(EM6), 1962.25. McKnight, C., Dillon, A., Richardson, J., Hypertext in Context, Cambridge University Press,Cambridge, 1901.26. Nixon, D., The Use of Frame Action to Resist Lateral Loads in Simple Construction,Canadian Journal of Civil Engineering, 8(4), 1981.27. Pierce, Joseph R., Toolbook Companion, Microsoft Press, Washington, 1990.28. Popov, E., On California Structural Steel Seismic Design, Earthquake Spectra, Vol. 2, No.4, 1986.29. Popov, E., and Black, R., Steel Struts Under Severe Cyclic Loading, Journal of theStructural Engineering Division, ASCE, Vol. 107, No. ST9, September, 1981.30. Popov, E.P. and Pinkney, R.B., Cyclic Yield Reversal in Steel Building Connections, ASCEJournal of the Structural Division, 95(ST3), 1969.12131. Popov„ E.P. and Stephen, R.M., Tensile Capacity of Partial Penetration Groove Welds,ASCE Journal of the Structural Division, 103(ST9), 1977.32. Nixon, D., The Use of Frame Action to Resist Lateral Loads in Simple Construction,Canadian Journal of Civil Enginerring, 8(4), 1981.33. Redwood, Richard, "Steel Detailing for Seismic Design Based on CAN/CSA-S16.1-M89",1990 Canadian Society of Civil Engineering Annual Conference, Hamilton, Ont., May 15-18, 1990.34. Robinson, Guner S., Proceedings WESTEX-86 IEEE Western Conference on Knowledge-Based Engineering and Expert Systems, Anaheim, Ca, 1986.35. Schmitke, C. and Kennedy D., Effective Lengths of laterally Continuous, LaterallyUnsupported Steel Beams, Canadian Journal of Civil Engineering, 12(3), 1985.36. Smith, Connie, Performance Engineering of Software Systems, Addison-Wesley, 1990.37. Vancouver Structural Engineers Group, Seismic Evaluation of Existing Buildings Seminar,Vancouver, June, 1992.38. Waterworth, John, Multimedia Technology and Applications, Ellis Horwood Limited,England, 1991.39. Wigan, M.R., "Engineering Tools for Building Knowledge-Based Systems on Microsystems",Microcomputers in Civil Engineering, 1, July, 1986.40. Wilson, Peter, "More Than Meets the Eye", Saturday Review, Vancouver Sun, Vancouver,B.C., 30 January 1993.41. Winter, G., Lateral Bracing of Columns and Beams, ASCE Journal of the Structuraldivision, 84(ST2), 1958.42. Wood, B, Beaulieu, D., Adams, P., Column Design of P Delta Method, Journal of theStructural Division, ASCE, 102(ST2), 1976.43. Wood, B, Beaulieu, D., Adams, P., Further Aspects of Design by P Delta Method, Journalof the Structural Division, ASCE, 102(ST3), 1976.122


Citation Scheme:


Citations by CSL (citeproc-js)

Usage Statistics



Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            async >
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:


Related Items