nbs special publication 693 - nist

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NBS SPECIAL PUBLICATION 693

U.S. DEPARTMENT OF COMMERCE {National Bureau of Standards

A Workshop on

STEEL RESEARCH NEEDSFOR BUILDINGS

MBMA- -

REPRODUC ED BY

NATIONAl TECHNICALINFORMATION SERVICE

u.s. DEPARTMENT OF COMMERCESPRINGFIELD. VA. 22161

he National Bureau of Standards' was established by an act of Congress on March 3, 1901. TheBureau's overall goal is to strengthen and advance the nation's science and technology and facilitate

t eir effective application for public benefit. To this end, the Bureau conducts research and provides: (1) abasis for the nation's physical measurement system, (2) scientific and technological services for industry andgovernment, (3) a technical basis for equity in trade, and (4) technical services to promote public safety.The Bureau's technical work is performed by the National Measurement Laboratory, the NationalEngineering Laboratory, the Institute for Computer Sciences and Technology, and the Center for MaterialsScience.

The National Measurement LaboratoryProvides the national system of physical and chemical measurement;coordinates the system with measurement systems ~f other nations andfurnishes essential services leading to accurate and uniform physical andchemical measurement throughout the Nation's scientific community, industry, and commerce; provides advisory and research services to otherGovernment agencies; conducts physical and chemical research; develops,produces, and distributes Standard Reference Materials; and provides'calibration services. The Laboratory consists of the following centers:

The National Engineering LaboratoryProvides and technical services to the public and private sectors toaddress national and to solve national problems; conducts research inengineering and applied science in support of these efforts; builds and maintains competence in the necessary disciplines required to carry out thisresearch and technical service; develops engineering data and measurementcapabilities; provides engineering measurement traceability services; developstest methods and proposes engineering standards and code changes; developsand proposes new engineering practices; and develops and improvesmechanisms to transfer results of its research to the ultimate user. TheLaboratory consists of the following centers:

The Institute for Computer Sciences and TechnologyConducts research and provides scientific and technical services to aidFederal agencies in the selection, acquisition, application, and use of computer technology to improve effectiveness and economy in Governmentoperations in accordance with Public Law 89-306 (40 U.S.c. 759), relevantExecutive Orders, and other directives; carries out this mission by managingthe Federal Information Processing Standards Program, developing FederalADP standards guidelines, and managing Federal participation in ADPvoluntary standardization activities; provides scientific and technological advisory services and assistance to Federal agencies; and provides the technicalfoundation for computer-related poliG,ies of the Federal Government. The Institute consists of the following centers:

The Center for Materials Science

•• Radiation Research• Chemical Physics• Analytical Chemistry

• Applied Mathematics• Electronics and Electrical

Engineering2

• Manufacturing Engineering• Building Technology• Fire Research• Chemical Engineering2

• Programming Science andTechnology

• Computer SystemsEngineering

Conducts research and provides measurements, data, standards, reference • Inorganic Materialsmaterials, quantitative understanding and other technical information funda- • Fracture and Deformation3

mental to the processing, structure, properties and performance of materials; • Polymersaddresses the scientific basis for new advanced materials technologies; plans • Metallurgyresearch around cross-country scientific themes such as nondestructive • Reactor Radiationevaluation and phase diagram development; oversees Bureau-wide technicalprograms in nuclear reactor radiation research and nondestructive evalua-tion; and broadly disseminates generic technical information resulting fromits programs. The Center consists of the following Divisions:

1Headquarters and Laboratories at Gaithersburg, MD, unless otherwise noted; mailing addressGaithersburg, MD 20899.

2Some divisions within the center are located at Boulder, CO 80303.3Located at Boulder, CO, with some elements at Gaithersburg, MD.

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BIBlIOGRAPHIC'UATASHEET (See Instruct/OIl.'

4. 'TITLE AND SUBTITLE

1. PUBLICATION ORREPORT NO.

NBS/SP-693

2. Perfonnln& OrIM. Report No J. Publication Date

~~ay 1985

A Workshop on Steel Research Needs for Buildings

5. AUTHOR(S)

Culver;'C.G.:,Iwankiw, N., and Kuentz, A.Ii. PERFORMING ORGANIZATION (If joint or other than NBS, see instructions'

National Bureau of StandardsU.S. Department of CommerceGaithersburg, NO 20899

7. Contract/Grant No.

8. Type of Report & Period Covered

Final

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, City, State, ZIP'

See title page

10. SUPPLEMENTARY NOTES

NBS Category No.

NBS·l&fO

Library of Congress Catalog Card Number:85-G00546

o Document describes a computer program; SF-ISS, F,PS Software Summary, is attached.

11. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significantbibliography or literature survey. mention it here'

This report identifies needed experimental and analytical research to advancethe state-of-the-art and improve safety and economy in the design, fabricationand construction of steel buildings, A five year plan for a coordinated researchprogram is included. Recommendations for research projects dealing with thefollowing topics are presented: Total building systems, connections and members,frames, seismic design, load and resistance factor design, fire protection, anddesign loads. The recommendations were developed at a workshop involvingparticipation by steel industry representatives, design professionals, Federalagency representatives and university researchers.

12. KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separote key words by semicolons)

Buildings; design; fire protection; loads; research; steel; structural engineering.

13. AVAILABILITY

[X] Unlimited

o For Official Distribution, Do Not Release to NTIS

C~~ Order From Superintendent of Documents, U.S. Government Printing Office. Washington. D.C.20402.

[]<] Order From National Technical Information Service (NTIS). Springfield, VA. 22161

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89

15. Price

USCOMM-OC 6043- P !'(I

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THIS DOCUMB!',iT HAS BEEN REPRODUCED

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( ti/

Steel Research Needs for Buildings

Proceedings of a Workshop Sponsored By:

National Bureau of StandardsNational Science FoundationAmerican Institute of Steel ConstructionAmerican Iron and Steel InstituteMetal Building Manufacturers Association

Held at the National Bureau of StandardsGaithersburg, MarylandMarch 5-6, 1985

Edited by:

Charles CulverNational Bureau of Standards

Nestor IwankiwAmerican Institute of Steel Construction

Albert KuentzAmerican Iron and Steel Institute

U.S. DEPARTMENT OF COMMERCE, Malcolm Baldrige, Secretary

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director

Issued May 1985

Library of Congress Catalog Card Number: 85-600546

National Bureau of Standards Special Publication 693Natl. Bur. Stand. (U.S.), Spec. Publ. 693, 89 pages (May 1985)

CODEN: XNBSAV

u.s. GOVERNMENT PRINTING OFFICEWASHINGTON: 1985

II

ABSTRACT

This report identifies experimental and analytical researchneeded to advance the state-of-the-art and improve safety andeconomy in the design, fabrication and construction of steelbuildings. A five year plan for a coordinated research programis included. Recommendations for research projects dealing withthe following topics are presented: total building systems,connections and membe r s, frames, se ismic des ign, load andresistance factor design, fire protection, and design loads. Therecommendations were developed at a workshop involvingparticipation by steel industry representatives, designprofessionals, Federal agency representatives and universityresearchers.

Keywords: buildings, design, fire protection, loads, research,steel, structural engineering.

iii

CONTENTS

ABSTRACT •• . . . . . . . . · . . · . . . . . • • iii

INTRODUCTION .. • • • • • • • • 0 • · . · . · . . · . . • 1

• • • • • • • • • • • fA • • • • • • • •

steel Industry Building Research

• • 1

· . . . • 4

• 8

· . . . . .· . . . . ... . .· . . .Research Needs Workshop

Background

Coordinated Research Program · . . . . . . . . . . • • 9

• • 0 •RESEARCH OPPORTUNITIES • • • •

• • · . . . .11

11

• •· . . .· . . .· . .• • •Total Building System •A.

AI: On-Site Fabrication • • .. · · • · • • • • •A2: Erection Procedures • · • • .. .. • • · • • ·A3: Innovative Systems • .. .. • • • • • .. • • • •A4: Large-Scale Testing • • • • · • • • · · • •

B. Connections and Members · · · · • • · · • • · • •

Bl: Steel Structures Exposed to SevereEnvironments • • · • .. · • .. · • • • • • ·B2: Performance of Connections in WeatheringSteel Structures • • • .. • • • · • · • · •

B3: Web Stiffeners • • • · .. • · • • .. · • · · •B4: Seated Beam Connections · • • · · • · • • ·BS: Semi-Rigid Connections • • · • • • .. · • · •B6: Beam-to-Column Connections .. • • • · • · • •B7: Load Deformation Behavior of Welds • • ..B8: Moment Connections to Column Webs • • .. • •B9: Lateral and Local Instability of Beams • • •BIO: Strength of Webs and Plates Under Fillet

Weld Groups • · · · • • • • · • • • • • •Bll: Composite Columns • • • • • • • · · • · • ·B12: Composite Floor Systems • • · · · • .. · · ·B13: Bar Joist Systems • · • • • • · · • • • · •B14: New Structural Members .. • · • • • • .. • • •

C. Frames • . • .. . . • · .. • • • · • • • • • · • •

Cl: Three Dimensional Behavior • • • • • • .. • •C2: Influence 6f Connections • • • • • • • • • •C3: Cladding and Infilling · · .. · · .. · · • · •C4: Lateral Deflection • • • • • • • • • • • • •

11121213

13

13

1414151616171818

19192020'21

21

21222223

iv

C5: Field Measurements • • • • • · • · e · • • • 24C6: Composite Construction • • • • e • • • • • · 24C7: Cold-Formed Construction • · • • • · • · • • 25C8: Non-Compact Sections • • • • • • • • • • • • 25

D. Seismic Design • • • • • • • • • • · • • • · • • 26

01: Behavior of Semi-Rigid Connections • • • • • 2602: Drift Control Criteria • • • • • • • • • • • 2703: Seismic Performance • e • · • • • • · • • • 2804: Steel Stud Walls • • • · • • • · · · · • • • 28D5: Beam-Column Joints • • • • • • • • • • • · • 2906: Beam-Columns • • • • • • • • • • • • • • • • 30D7: Tubular Members • • • • • • • • • · • • • • 3108: End-Plate Beam-to-Column Connections • • • • 32D9: Bolted Web Moment Connections • • • • • • • 33010: Bracing Connections • • • · • • • • • • • · 34011: Viscoelastic Damping • • • • • • • • • • • • 35D12: Ductility Demand · • • • · • • • • • • • • • 36013: Braced Frame Stability • · · • · · · • • • • 36014: Lateral Bracing • • · • • • • • • • • · • • 37DIS: Overall System Response • • • • • • • • • • 38016: Evaluation of Existing Buildings • • • • • • 39

E. Load and Resistance Factor Design • • • e • • • • 40

El: Connections With Oversize Holes • • • · • · 40E2: Web Crippling • • • • • • • • • • • • • • • 40E3: Technology Transfer e · • • • · · · • · • · 41E4: Resistance Factors · • • • • · • • • · • 41E5: Serviceability Criteria • • • • • • • • • • 42E6: Lateral Motion Criteria. • • · · • • • · • • 43E7: Vibration Control for Light Floor Systems • 43E8: Plastic Design · • · • • • • • • • • • • • · 44E9: System Reliability • • • • • • • • • • • e • 44ElO: Wind and Seismic Effects • • · • • • • • • • 45Ell: Existing Buildings • • • • • • • • • • • • • 46

F. Fire Protection • • • • • • • • • • • • • • • • • 47

Fl: Fire Resistant Design • • • • • • • • • • • 47F2: Design Aids · • • • · • • · • · • · · e · • 47F3: Shop Applied Fire Protection • • • • • e • • 48F4: Large Area/Large Volume Structures • · • • • 49F5: Fire Research Review • • • • • • • • • • • • 49

G. Design Loads . • • • • • • • • e · • • • • · • • 49

Gl: Crane Loads • • · • · • • • • • • · • • • • 50G2: Drifted Snow · · • · • · • · • · • · • • • • 50G3: Cladding Behavior • • • • • • • • • • • • • 50

v

G4: Wind Loads on Low Rise Buildings • • • • • •G5: Internal Pressure Loading • • • • · • • • •G6: Building Response to Winds • · · • · • •G7: Large Area Roofs . • • • • • • • • • • • • •

• • • e • • • • • • • • • • • • • • • • •

• • • • • • • • •

51515252

54

55

55

67

71

• •

• •

• •

• •

• • •

• • • •

• •

· . .• •

• •

• • • • •

· . .• •• • •• • • •

Appendix A - Workshop Keynote Session

Appendix B - Workshop Program

Appendix C - Workshop Participants

APPERDICES • • •

ACKNOWLEDGIIElnS

vi

INTRODUCTION

BACKGROUND

Steel construction is an important segment of the u.s.economy. Approximately 94 percent of the output of thefabricated structural metal industry is consumed by constructionmarkets. Industrial and commercial building construction accountfor about two-thirds of this output. Over the past decade thefabricated structural steel market has varied from 3.5 milliontons per year to almost 6 mi 11 ion tons per year.

Since its formation more than 60 years ago, the AmericanInstitute of Steel Construction, Inc. CAISC) has been the U.S.trade association for the structural steel fabrication industry.The Institute has provided information for structural steelengineering and construction such as the much referenced designspecification, standard shape properties and design aid's, whichare published in the AISC Manual, and has provided services inthe form of technical seminars and conferences, marketing andresearch. The latter activity, sponsored at leading universitiesand laboratories, has contributed the substance that makes theAISC Specification a world-class design standard. The steelindustry has continued to provide funds for research programseven throughout the recent recession. The commitment of AISC andits membership to future research is strong. This research willhelp advance the state-of-the-art of steel design towards a newgeneration of AISC Specifications, starting with the Load andResistance Factor Design (LRFD) Specification and, improveddesign procedures.

Eight editions of the AISC Manual and Specification provideclear historical evidence of the technical work that has beendone and the progress achieved. Plastic des ign, compos i teconstruction, and now LRFD are some of the significant advances.Beginning in 1964, AISC began publishing the quarterlyENGINEERING JOURNAL, which contains articles of current interestto practicing designers. This pUblication provides a convenientoutlet for distribution of new design criteria based on recentlycompleted research and it describes in greater detail thedevelopments in steel design practice.

In addition to its Manual and ENGINEERING JOURNAL, AISC alsoperiodically pUblishes special texts on particular topics.During the past 2 years, two books have been prepared: DetailingfQL ~~l Construction and Engineering fQL Steel Constructionwhich contain updated steel design and detailing practice.Ongoing AISC research has provided important input to thesebooks.

The American Iron and Steel Institute (AISI), incorporatedin 1908, is a non-profit association of the iron and steelindustry. Its purposes are 1) to collect statistics and other

1

information about the industrY1 2) to engage in investigationsand research1 3) to provide a forum for the exchange ofinformation and discussion of problems relating to the industrY1and 4) to promote the use of iron and steel. Instituteactivities embrace research and technology, engineering,collection and dissemination of statistics, public distributionof information about the industry and its products, publicaffairs, and discussion of industrial relations including healthsafety, and hygiene. The Institute has members in the UnitedStates, Canada and Latin America.

Promotional activities of the Institute include appliedresearch, product pUblicity, booklets, trade show participation,motion pictures, seminars, and educational programs. Many ofthese activities are carried out in cooperation with importantcustomer associations such as the American Institute of SteelConstruction (AISC).

AISI staff engineers work with public agencies and privateorganizations to promote maximum use of steel mill products inconstruction. They are responsible for industry activitiesrelated to construction codes and regulatory standards, and forresearch and studies on fire protection of steel in buildings andseismic-resistant design. These activities benefit architects,design engineers, and the public, and have helped introduce newstandards for steel construction and the revision of manyobsolete code requirements. These changes have broadened the useof conventional steel construction, stimulated the development ofnew types of cold-formed steel floor, roof, and wallconstruction, and reduced building and highway costs. In orderto carry out this code-related responsibility more effectively,the Institute maintains field offices in cities throughout theUnited States.

Thirteen Product Promotion Committees within AISI carryonselected research and promotion programs of specific interest totheir members who produce a particular product. Committeemembers include producers of specialty steels such as stainlesssteel and tool steel, and producers specifically interested insuch mill products as hot rolled and cold finished bars, sheetand strip, large diameter line pipe, steel plate, and structuralsteel.

The Metal Building Manufacturers Association, Inc. (MBMA),organized in 1956 with 13 companies, grew to 35 member firms in1980. As the industry matured, the number of Association membersdecreased to 27 in 1985, principally due to mergers consumatedbetween member companies. Association members presently maintain71 manufacturing plants in 25 states, plUS additional facilitiesin Canada, Europe, Australia, South America and the Middle East.Pre-engineered metal building systems are sold through a networkof over 8,800 bUilding contractors.

At present, MBMA manufacturers account for well over 50% ofthe total market for low-rise, non-residential construction.

2

Achieving a high in 1983 of 55.1%, pre-engineered metal buildingsmust now be regarded as the "conventional" way to build 1 and 2story commercial, community, and industrial buildings. Sales ofmetal building systems by MBMA members, who presently representapproximately 90% of the pre-engineered market, have topped thebillion-dollar mark in five of the past six years. Since a metalbuilding system only accounts for approximately 20% of the totalcost of a building project, the 1984 industry sales high of $1.33bill ion represents about $6.7 bill ion of in-place construction.Steel tonnage rose 33% in 1984 to a record high of 1.14 milliontons.

In close cooperation with AISC and AISI, MBMA attacks abroad range of problems facing the steel industry. Throughvarious standing committees, MBMA marshalls its forces throughresearch and other activities to develop and support new designstandards, improve the provisions of model building codes,develop new construction practices and safety regulations as theyapply to the metal building industry, and generally advance thestate-of-the-art in the design and construction of steelbuildings. The MBMA Committees include the Technical,Construction, Mill Relations, Marketing Communications, FireProtection and Related Insurance Matters, Public Relations, andPost-Disaster Committees, to name just a few. Although theTechnical Committee is charged with the primary responsibilityfor developing and monitoring the research effort, appropriateinteraction between all committees is maintained to ensure thatthe industry produces a high quality, reliable building while, atthe same time, adequate attention is given to the need tosafeguard economy.

Recently, MBMA joined with AlSl to explore ways to obtaingreater acceptance of metal building systems by industrial parkdevelopers and the financial community. MBMA is also working toassist the Metal Building Dealers Association (MBDA) and itsmembers in reaching these and other important interests.

One of the primary objectives of the Metal BuildingManufacturers Association, Inc., is to collect, analyze, anddisseminate information. These data are then offered to membercompanies, customers, architects, engineers, and students atengineering schools across the country in the most comprehensivemanner possible. By sharing and publishing the results ofresearch, MBMA seeks to generally improve the understanding andacceptance of metal building systems. The data collected throughresearch are pUblished in various documents. The METAL BUILDINGSYSTEMS MANUAL, which was updated for the third time in 1981 bythe Technical Committee, incorporated the codified standards onwind load criteria from the Western Ontario wind tunnel researchproject. The Technical Committee also published a structuraldesign text book entitled, ~ Design Q! ~~g Story RigiQFrames, a Crane Manual f2£ M~ Building Systems, and cooperatedwith MBDA in the publication of the book entitled, Metal BuildingSystems. This year will mark the completion of an entirely newpublication, ~~ ~Qing Systems Manual, which is a primer

3

on design and construction practices for low-rise, nonresidential construction and reflects the end result of threedecades of research by the industry. Many of the provisionscontained in the Design Practices section of the Manual aregenerally applicable to all types of low-rise construction.

STEEL INDUSTRY BUILDING RESEARCU

There is a continuing need for steel research related tobuilding construction. The steel industry, through the AmericanInstitute of Steel Construction (AISC), the American Iron andSteel Institute (AlSI), the Metal Bui lding ManufacturersAssociation (MBMA) and individual companies, has sponsoredresearch on steel building construction for over 70 years.Currently, the industry is pursuing an aggressive program ofcollaborati ve research and development with a var iety oforganizations.

The AISC research activities have always been well definedand regularly monitored by its Committee on Steel StructuresResearch and the engineering staff. Smaller project task groupscomposed of industry personnel and outside experts also helped toguide research progress. In most cases, university graduatestudent teams performed the work under the leadership of anexperienced faculty investigator. Results of the research arenot only documented in a detailed final report, but are alsodisseminated in useable form to the structural engineeringprofession through AISC seminars, publications, and Specificationrevisions.

The main thrust of steel research in the 1950's was plasticdesign. Annual funding in the $100,000 to $200,000 range wascommitted by AISC to research in those years, which culminatedwith the introduction of the AISCSpecification Part 2 on plasticdesign, and with several beneficial changes in allowable stressdesign due to a recognition of steel's ductility.

From the mid-60's to the 70's, the AISC total researchfunding declined to about $60,000 - $70,000 per year. In the1980's, during a very competitive construction marketenvironment, greater resources were again devoted to steelresearch on the order of $150,000 - $200,000 per year.

Typically, a single AISC research contractor receives$20,000 to $50,000 annually, thereby permitting AISC to support 5to 10 different projects.

Since the heyday of plastic design studies, the last 20years of AISC research has been primarily focused on connections- their reliability and economy. The members of AISC, includingstee I fabr icator sand professiona 1 member s, recognize that theintegrity of steel structures depends, to a large extent, on theperformance of connections. High strength bolts, weldments,composite beams, end plate and shear plate connections have been

4

included in the AISC research program during recent years.

Considering the number, complexity, and potential scope ofthe various technical questions posed by engineers, architects,and fabricators, the AISC research budget by itself does notpermit much broadly based basic research in structural steel.Most AISC studies are short range and aimed at developing answersto immediate design problems. Interspersed with this necessaryreactive work are some developmental projects aimed at innovativeconcepts or procedures that will improve the design of steelstructures. This AISC effort is extended by cooperativesponsorship of larger scale projects with organizations such asthe National Science Foundation (NSF), the National Bureau ofStandards (NBS) and the Metal BUildings Manufacturers Association(MBMA). Special attention is given to the coordination of AISCresearch with that of the American Iron and Steel Institute(AISI). The latter organization is making significantcontributions towards longer range building research. Tomaintain technical liaison with related research councils, AISCalso supports the work of the Research Council on StructuralConnections, the Structural Stability Research Council, theWelding Research Council, and the Steel Structures PaintingCouncil.

The AISI structural steel research program is monitored bythe Committee of Steel Plate Producers and the Committee ofStructural Steel Producers. The program has been in operationsince 1963. The research covers markets which utilize structuralsteel and steel plate, with special emphasis on heavyconstruction. To serve the needs of the majority of users,concentration has been on buildings and bridges.

A prime objective of this research in steel utilization isthe creation of new or improved design procedures for structuralsteel and plate. These procedures frequently form the basis ofindustry specifications and government codes. A secondaryobjective is the development of data to mitigate unnecessarilystringent provisions in various design specifications.

The program began with a budget of $250,000 per year andclimbed to $600,000 by 1970. Then in the 70's the researchfunding gradually declined back to the $250,000 figure. The1980's have seen an increase to $350,000 to meet new challengesin the building construction market. The program consists of anongoing series of projects - typically 12 are underway at anytime - encompassing analytical studies, physical testing andpreparation of design manuals. Some are started and finished thesame year. More complicated studies can encompass a four- tosix-year period. The program recently marked an importantmilestone with completion of over 100 individual projects sinceits inception.

The selection of research projects begins with arecommendation from an Engineering Subcommittee consisting ofengineers fromAISI member steel companies. The final approval

5

is made by consensus of 'the Committees of Structural Steel andSteel Plate Producers.

Once a project is approved, a member of the EngineeringSubcommittee is appointed project supervisor, overseeing a taskforce that will plan and direct the project from commencement tocompletion to ensure that its objectives are met. Task forcemembers can include consultants, educators, engineers, scientistsgovernment and code officials, and steel industry personnel.

The research is performed primarily by universities, withsome done by private research and consulting organizations, andsome by steel company research laboratories. Over 20universities have taken part in the program.

When a project has been completed, the results are widelydisseminated. One technique is to hold seminars in key cities todiscuss the project findings. Frequently, the full projectreport is printed in an AISI ·Steel Research for Construction·bulletin - 27 have been printed to date - with copies madeavailable in response to requests.

AISI's research over the years on beam, column and framebeha v ior has resu 1 ted in s ignif icant improvements to theprovisions of various design specifications - increasing both theeconomy and safety of steel construction. Significant researchaccomplishments include:

LQgg and Resistance Factor Design

Studies begun in 1970 resulted in new limit state criteriacontaining provisions for loads and load-combinations andrules for the proportioning of structural members and connections. Work continues to improve the reliability ofthe design format.

~ 1 Construction~ NinQ Moment Connections

The investigation begun in 1977 demonstrated the viabilityof the design procedure and led to a better understandingof the effect of connection flexibility on frame stability.

Connections

Studies on single plate framing connections resulted inpublication of guidelines for the design of theseeconomical connections and provided a clear understandingof their ductility and moment rotation capacity.

In addition, the Institute's studies of fire hazards and fireprotection have contributed to new regulatory concepts relativeto the use of non-combustibles, matching protection requirementsto the sever i ty of hazards, and avo idance of imba lance in firerisks. The result is greater fire safety, often at lowerbuilding costs.

6

The MBMA research acti v i ty has culmina ted in new andimproved design specifications introduced from time to time intothe AlSC and AlSI Specifications and the MBMA Design PracticesManual. The current provisions contained in these documentsrelative to end-plate connection design, web crippling, thedesign of tapered members, stability and strength of cold-formedpurlins and girts, are but a few of the more notable examples.The recent trend in research activity by MBMA is to focus onbuilding "system" behavior as compared to that of individualcomponents. Thus, new specification provisions are presentlybeing prepared with regard to the required strength, stiffness,and bracing requirements for complete roof systems.

In 1976, MBMA assumed a leadership role in developing newwind load criteria for the design of low-rise buildings. Duringthe ensuing period, extensive research has been conducted in theBoundary Layer Wind Tunnel Laboratory at the University ofWestern Ontario under the joint sponsorship of MBMA, AISI and theCSICC. This research has culminated in new wind load provisionswhich have been accepted in the United States and Ganada by anumber of the appropriate code bodies. Research on wind effectsis continuing at the present time.

MBMA research activities are originated and closelymonitored by various small task groups or subcommittees composedof industry personnel, outside experts, representatives from AISCand AISI, and staff personnel. lnspite of recent dips in theeconomy, MBMA's basic commitment to research has been steadfastlymaintained through the years and the present level of activity isin the $100,000 - $150,000 per year range. The number ofindividual projects vary from year to year. During the currentyea r , for ex amp Ie, six s epa rat e pro j e ct s are un d e r way.Additionally, MBMA awards two fellowships annually to engineeringstudents pursuing a course of study related to steel buildings.The fellowship objective is to encourage creative designinvestigation of specialized areas relative to fabricated metalbuilding systems.

The MBMA research effort is extended by cooperative effortswith organizations such as AISC, AlSI, and hopefully, in theimmediate future, NSF. MBMA also supports the researchactivities of, and maintains technical liaison with, the WindEngineering Research Council, the Structural Stability ResearchCouncil, the Welding Research Council, the Research Council onStructural Connections and the Building Seismic Safety Council.

Although the steel industry is now experiencin.g difficulteconomic conditions, its commitment to continued and expandedsteel research is evident. With the cooperation and assistanceof government and the engineering community, the industry isconf iden t that this e·ffort wi 11 1 ead to new techno log ica 1advances that will enhance the state-of-the-art of steel designand construction.

7

RESEARCH NEEDS WORKSHOP

Recognizing the importance of steel research and the needfora coordinated, well-planned program, AISC, AISI, MBMA and theNational Bureau of Standards (NBS) decided in 1984 to organize aworkshop for the purpose of identifying needed research. TheAISC Research Committee, the AISI Building Task Force and the NBSCenter for Building Technology developed the initial plan for theworkshop. Subsequently, a steering committee consisting ofdes ign profess iona 1 s, industry representa ti ves, governmentrepresentatives and university researchers was established toplan the technical details.

This report constitutes the proceedings of the workshop onSteel Research Needs for Buildings. The workshop objective wasto develop recommendations for experimental and analyticalresearch needed to advance the state-of-the-art and improvesafety and economy in the design, fabrication and construction ofsteel buildings. The recommendations are intended for use bygovernment, industry, and the research community in establishinga cooperative program. Research in the following areas isconsidered:

Total BUilding System

Connections and Members

Frames

Seismic Design

Load and Resistance Factor Design

Fire Protection

Design Loads

workshop participants included representatives from the steelindustry, design professionals, Federal agency representativesand university researchers.

The opening session of the workshop included presentationsby representatives from the Office of Science and TechnologyPolicy, the National Bureau of Standards and the steel industry.These presentations are included in Appendix A. They provide aperspective on structural steel usage in buildings, considercooperative research efforts involving industry and government,and provide background material for the workshop recommendations.

The recommendations were developed in two days of intensivesubcommittee meetings and plenary sessions. Draftrecommendations developed by the participants prior to theworkshop served as a starting point for the subcommitteediscussion. Each subcommittee focused on one of the sevenresearch areas covered by the workshop. A plenary session

8

following the subcommittee meetings provided all participantswith the opportunity to comment on recommendations developed byeach subcommittee. This procedure was repeated to achieveconsensus among the participants on the final recommendations.

COORDINATED RESEARCH PROGRAM

The workshop recommendations provide the basis for acomprehensive program to improve safety and economy in thedesign, fabrication and construction of steel buildings.Activities in this direction are underway. AISC is planning aspecial educators session on May 21,1985 in Chicago prior to itsInternational Engineering Symposium on Structural Steel with thetheme, "Opportunities for Structural Steel Research". Industryand government speakers will outline the major problem areas.Approximately 100 faculty from across the country are expected toattend.

The level of effort required for each workshoprecommendation is indicated in terms of man years. A preciseestimate of the funds required cannot be determined withoutdetailed planning for each project. Costs for test specimens,computer time, laboratory personnel, etc., need to beestablished. The total program represents a substantial effort.A well planned multi-year effort using results obtained in eachphase to plan subsequent work is clearly more cost effective thansimultaneous initiation of work on each recommendation.Recognizing this, the workshop Steering Commmittee developed thefive-year plan given in Table 1. Recommended fundingrequirements were established on the basis of the immediacy ofthe need for the information by the design profession, theabi 1 i ty to achie ve synerg ism between research proj ects and theopportunity to obtain results as rapidly as possible. It isanticipated that funding would be provided by the private sectorand government organizations.

An effective research program requires a coordinated effort.Industry representatives, government representatives, designprofessionals and researchers should be involved. This can bestbe achieved by establishing a steering group to provide guidancein establishing reqUired funding levels for the variousactivities. The goal of the group would be to provide a vehiclefor implementing the research results to achieve rapid"improvement in the des ign and construction of stee 1 bui ld ings.This group would meet on a regUlar basis, monitor progress of theresearch and upda te the research needs. Establ ishing thissteering group should be given priority consideration.

9

TABLE 1

FIVE YEAR PLAN

structural Steel Research for Buildings

I---------------·---..----.. FUNDS (in. t~~~sands of d~~~~~~~___

Program Year Year Year Year YearArea 1 2 3 4 5

-----"--- _...,-----...._----Total Building 300 300 200 200 200

System

onnections and 800 1000 1000 600 600Members

Frames 700 800 1000 900 500

Seismic Design 700 1000 1000 600 300

Load and Resistance 600 800 800 1000 1000Factor Design

ire Protection 300 400 300 200 100

esign Loads 600 700 700 500 300

--"--'---"-'-'-'-'-'-~----_..-

TOTAL 4000 5000 5000 4000 3000

10

RESEARCH OPPORTUNITIES

The workshop recommendations provide opportunities forconstructing safer and more economical steel buildings. Theyrepresent a comprehensive program with emphasis on:

o characterizing the behavior of individualstructural components

o establishing the performance of total buildingsystems

o developing improved design procedures anddesign criteria

They cover the important areas of building design. Synthesis ofexisting information, exper imental work and analytical studiesare included.

The individual recommendations should not be considered inisolation. Although they are grouped according to the researchareas dealt with at the workshop, other groupings are possible.In addition, many of the recommendations are interrelated. Forexample, the research on frames and total building systems shoulddraw upon the work on connections and individual members.Similarly, work on load and resistance factor design encompassesboth structural elements and systems.

Each recommendation deals with an important problem area.It is assumed they will all be included in a coordinated researchprogram and therefore they are not listed in priority order. Thelevel of effort for each recommendation represents an estimate ofthe professional manpower required. Detailed research plans foreach project are required to establish specific fundingrequirements.

A. TOTAL BUILDING SYSTEM

Much of the research in the past has concentrated on thebehavior of individual components and subassemblages of portionsof bUilding systems. Consideration should be given to the totalbuilding system and various aspects of the building process,including fabrication and erection, to achieve economy for steelbuildings.

RECOMMENDATION AI: ON-SITE FABRICATION

STUDIES SHOULD BE CONDUCTED TO EXPLORE THEFEASIBILITY OF ON-SITE FABRICATION OFSTRUCTURAL STEEL COMPONENTS.

The construction industry has made considerable progress in

11

developing improved techniques for the fabrication and erectionof concrete buildings. Similar innovative erection practicesshould be developed for steel buildings. One possibilityincludes utilizing mobile fabrication plants set up at thebuilding site to manufacture large units that could notordinarily be transported.

Needed research includes identification of fabricationactivities more economically carried out on-site rather than in afabrication shop. Possibilities include fabrication of steelplate shear wallS and large tilt-up frame assemblies.Constraints imposed by weather conditions, on-site spacelimitations, etc., should be considered. Costs associated witheach possible on-site activity should be established and comparedwith current fabrication and transportation costs.

A two man-year level of effort is required.

RECOMMENDATION A2: ERECTION PROCEDURES

IMPROVED COST EFFECTIVE TECHNIQUES SHOULDBE DEVELOPED FOR ERECTING STEEL BUILDINGS.

A research program should be undertaken to develop acoordinated approach to the fabrication and erection of steelbuildings. The program should involve a multidisciplinary groupcomposed of designers, detailers, fabricators, and mill anderection engineers. Techniques used on a recently completed 72story bUilding in Toronto, Canada such as the use of oversizedelevators and the panelizations of the steel and granite skin canprovide background data. Opportunities to minimize field weldingand simplify connection details and development of new framingdesign concepts should be studied.

A two man-year level of effort is reqUired.

RECOMMENDATION A3: INNOVATIVE SYSTEMS

INNOVATIVE STRUCTURAL FRAMING SYSTEMS SHOULDBE DEVELOPED FOR STEEL BUILDINGS.

Development of the tube concept as a more efficientmechanism than traditional moment resistant or braced frames forresisting lateral loads resulted in more economical high risestructures. New structural systems employing innovative conceptsthat take advantage of the unique a ttr ibutes of stee 1 elementsshOUld be developed.

A task force composed of arcbitects and structural engineersshould be established to identify innovative structural framingconcepts. Analytical studies of these concepts should be carried

12

out and cost comparisons made with traditional framing systems.


RECOMMENDATION A4: LARGE-SCALE TESTING

LARGE-SCALE TESTS SHOULD BE CONDUCTED TOESTABLISH THE PERFORMANCE OF INNOVATIVESTRUCTURAL COMPONENTS AND SYSTEMS.

Innovative systems may employ concepts not amenable totraditional structural analysis. In these cases, experiments arerequired to evaluate the performance of such systems, identifythe limit states and establish adequate levels of safety. Largescale tests will be required to minimize scale effects inherentin testing small-scale laboratory specimens or to determine howthe scale effects can be taken into account.

A mechanism should be established for conducting theseexperiments utilizing existing large-scale structural researchfacilities throughout the United States.

A multi man-year level of effort is required.

B. CONNECTIONS AND MEMBERS

From the fabricators' point of view, except for the cost ofmaterial, freight, shop drawings, and cutting members to length,all other costs are associated with providing connections. Fromthe erectors' point of view on a high rise building, about 30 to40 percent of the erectors' cost is in making the connections.Connection design is important in achieving safe structures.Continued research is needed for improved understanding ofconnection behavior to achieve more economical and safestructures.

RECOMMENDATION Bl: STEEL STRUCTURES EXPOSEDTO SEVERE ENVIRONMENTS

RESEARCH IS NEEDED TO DETERMINE THE EFFECTSOF SEVERE ENVIRONMENTS (COLD AND MOISTURE)ON COMMONLY-USED FABRICATION PROCEDURES.

Commonly used fabrication procedures and steel materialshave resulted in several failures in steel structures exposed tolow temperatures. These are design, fabrication and constructionrelatd issues.

Commonly used cutting techniques often result in plate edgeconditions that are not suitable for low temperature service.

13

Welded details can result in crack-like conditions with backingbars, runoff tabs or flame cut preparations and transitions.High deposition sUbmerged arc weldments can result in lowfracture resistance.

Experimental and analytical studies are needed to evaluatethe suitability of using current fabrication procedures forexposed building structures with comonly used steel materials(i.e., A36, A572, A588).


RECOMMENDATION B2: PERFORMANCE OF CONNECTIONS INWEATHERING STEEL STRUCTURES

DESIGN RECOMENDATIONS NEED TO BE DEVELOPED FORBOLTED CONNECTIONS IN BARE WEATHERING STEELSTRUCTURES, SUCH AS BUILDINGS OR TOWERS, TOINSURE THAT THE INTEGRITY OF THE CONNECTIONSIS NOT DEGRADED WITH CONTINUED EXPOSURE TOWEATHERING.

Guidelines have been developed for bolt spacing and edgedistance limitations that appear to be reqUired to prevent severebowing caused by corrosion between faying surfaces of lappedconnection elements. This condition arises because the corrosionresistance of weathering steel within such lapped areas is nobetter than that of carbon steel.

Tests of connections that have been exposed for significanttime periods should be conducted to determine how such weatheringhas affected strength and ductility. Important variables wouldinclude bolt spacing and edge distance, bolt type andinstallation method, time and conditions of the exposure, type ofloading (tension, compression, shear-static or cyclic), etc.Possible repair methods for such joints should also beinvestigated. Evaluations of improved methods for making suchdetails (washers for self-draining features; coatings or sheetsof adhesives or mastics for the lapped areas) should be made.


RECOMMENDATION B3: WEB STIFFENERS

PROCEDURES NEED TO BE DEVELOPED FOR BOTH DESIGNAND DETAILING OF BEARING AND TRANSVERSE WEBSTIFFENERS ..

Significant research has been completed on the strength ofwebs SUbjected to concentrated loads or shear. The design rulesin the AISC specification give, with reasonable reliability, the

14

strength of unstiffened webs. When stiffeners are required tosupport the loads or shear, the current methods for detailingstiffeners are difficult to document because little research isavailable. For example, bearing stiffeners are commonly fittedbetween the flanges at great expense, but no data are availableto support this practice. The bearing stiffeners are sometimesdesigned to carryall the load in spite of the ability of the webitself to carry a significant portion of the load. The design ofthe bearing stiffener-web combination as a column is based onrules of thumb for K factors and the portion of the web actingwith the stiffener. When stiffeners are required to improve theshear buck ling capaci ty of a web, they must ha ve enough moment ofinertia to prevent the web from buckling at the stiffenerlocation. Rules of thumb or approximate energy solutions areused to develop design rUles. No experimental evidence isavailable to verify the recommendations.

An analytical and exper imental program is needed to studythe problem of bearing stiffener and transverse stiffenerbehavior and design for static loading. Different web depththickness ratios should be considered to cover the range ofrolled beams and practical plate girders. Specific attentionshould be given to the effect of the detail at the far end of thestiffener on the stiffener behavior. A few full size specimensshould be tested to verify the analytical studies.

A two to three man-year level of effort is required.

RECOMMENDATION B4: SEATED BEAM CONNECTIONS

TABULATED ULTIMATE STRENGTH DESIGN VALUES ARENEEDED FOR BOLTED AND WELDED SEATED BEAMCONNECTIONS.

Seated connections are often used in steel construction asan erection necessity. Although allowable stress values havebeen tabulated in the AISC manual for many years, there are fewrecorded tests. The tabulated values are based on a hypotheticalstatic model. Both welded and bolted seated connections areinvolved. It is thought that the present load tables may beexcessively conser vative.

Experimental and analytical studies are required to developan ultimate strength design basis for seated connections. Bothwelded and bolted connections should be considered and thestudies should include both stiffened and unstiffened seats.

A one man-year level of effort is required.

15

RECOMMENDATION B5: SEMI-RIGID CONNECTIONS

MOMENT-ROTATION AND DUCTILITY CHARACTERISTICSFOR VARIOUS TYPES OF CONNECTIONS ARE NEEDED TOFACILITATE TYPE 3 CONSTRUCTION.

Analytical techniques are now in existence and are beingrefined via the computer to analyze and design steel frames withflexible connections. However, a major shortcoming that hasprevented regular design office use of Type 3 semi-rigidconstruction has been lack of reliable data on the structuralcharacteristics of flexible connections, namely their momentrotation curves. Detailed published information on the nonlinearmoment-rotation performance of the connection is limited and notreadily available to the practicing engineer. Thus, onlyidealized Type 1 (rigid) and Type 2 (simple) framing have beenemployed in bUildings. More use could be made of simple low costsemi-rigid connections, with full recognition of their stiffness,strength and ductility, if more complete information wasavailable on their moment-rotation characteristics.

Additional tests are needed to determine typical momentrotation curves for a given type of connection and theirsensitivity to the major design variables. This work, ifsupplemented by extensive computer analyses should provide asolid basis for generalized methods to approximate momentrotation properties for any connection. Flexible flange plateand cap and seat angle connections have been studied to someextent. Continuation of this work is desirable to establish aval id and complete moment-rotation data base for future designapplication. It is expected that such research would provide thenecessary impetus for more efficient and economical steel designby demonstrating a good alternative to the often restrictive andexpensive fully rigid frame.

A three man-year level of effort is reqUired.

RECOMMENDATION B6: BEAM-TO-COLUMN CONNECTIONS

A COMPREHENSIVE RESEARCH PROGRAM SHOULD BE UNDERTAKEN TO DEVELOP PROBABILITY-BASED DESIGN CRITERIAFOR BEAM-TO-COLUMN CONNECTIONS.

Continued research on connections has led to the developmentof design procedures for designing frames with partiallyrestrained connections. Parallel to this analytical advancement,a coordinated effort is necessary to collect reliable momentrotation data, and to produce optimal data for the development ofprobability-based design criteria.

An experimental and analytical research program includingthe following work shOUld be undertaken:

16

o Collection of moment-rotation data for connectionsand evaluation and development of analytical models(see RECOMMENDATION B5).

o Systematic categorization of all connection typesand the classification of all relevant limit states.

o Development of a computerized data bank on all availableexperimental and analytical research results relating toconnections.

o Identification of the gaps in the available data. Moderntests on many types of connections, performed on thebasis of statistical methods, are not available (e.g.,column bases, anchorages).

o Development and implementation of a plan to obtain theneeded data.

o Development of a logical design method for proportioningthe beams, connections and the columns.

o Verification test of a full-scale flexibly-joined frame.

o Systems reliability analysis of all connection types todetermine the reliability against the limit states.

o Development of design criteria which result in optimalreliabiity and economy.

A multi year level of effort is required.

RECOMMENDATION B7: LOAD DEFORMATION BEHAVIOROF WELDS

ACCURATE DETERMINATION OF THE LOAD-DEFORMATIONBEHAVIOR FOR ALL WELDING PROCESSES, WELDSTRENGTHS, AND LOAD CONDITIONS IS NEEDED.

Analytical work has been published which substantiatesexperimental results indicating that transversely loaded filletwelds are stronger than longitudinally loaded welds. Inaddition, stress concentrations are known to affect weldstrength. Current information is based on tests under nearoptimum conditions using E60 electrodes.

Research should be undertaken to investigate the range ofva riab 1 e s whi c h affect we 1d strength. In par ticu 1 a r, s t r eng t hand ductility should be investigated considering load orientationwith respect to weld axis, weld wire strengths, and weldingprocesses. In addition, single-pass versus multipass weldsshould be studied to determine the effect of the root pass andmixing of base metal with weld metal. Finally, the effects of

17

stress concentrations with regard to load orientation should beinvestigated.

A one to two man-year level of effort is required.

RECOMMENDATION B8: MOMENT CONNECTIONS TO COLUMNWEBS

DESIGN CRITERIA AND DETAILING PROCEDURES ARE NEEDEDFOR MOMENT PRODUCING CONNECTIONS MADE DIRECTLY TOTHE COLUMN WEB.

In cases where end plate connections or other momentproducing connections (such as single plate framing connections)are framed into a column web, little is known regarding theeffect on the web.

Research should be initiated to determine allowable beammoments for various web and end plate configurations.Determination should also be made as the most economicalfabrication method to be used to strengthen the column web ifrequired. The project would require both physical testing andanalytical work.


RECOMMENDATION B9: LATERAL AND LOCAL INSTABILITYOF BEAMS

THE EFFECT OF SIMULTANEOUS LATERAL AND LOCALINSTABILITY ON STRENGTH AND DEFORMATION CAPACITYOF BEAMS SHOULD BE STUDIED FOR LRFD.

The lateral and local instability provisions for beams inthe proposed LRFD specification are similar to those in thecurrent allowable stress design (ASD) for compact beams, notthose required for beams in plastic design (PD). Which set ofprovisions to adopt depends on the inelastic deformation capacityto be achieved or required in design.

Research is needed to examine the inelastic behavior ofbeams with width-to-thickness ratios of flange and web andlateral bracing spacings at the limits specified in ASD and PD.Special factors to consider inClude:

o High strength steel beams, repeated and reversedloading, etc.

o The range of parameters to be studied inClude:bf 12tf, d/tw and £b and the values shouldrange between those specified in ASD and PD.

18

An exper imental program of research should include full-scaletesting of continuous beams and single-story frames. Theanalytical research should include nonlinear, inelastic frameanalysis to determine required deformation capacity.


RECOMMENDATION BIO: STRENGTH OF WEBS AND PLATESUNDER FILLET WELD GROUPS

DESIGN AND DETAILING PROCEDURES ARE NEEDED FORDETERMINING WEB OR PLATE THICKNESS REQUIRED TOMATCH FILLET WELD STRENGTH.

Current practice uses a method which equates fillet throatallowable stress to web or plate allowable shear stress in orderto determine the web or plate thickness required to match thefillet weld strength. For shear alone, this method is correctfor a directly welded web connection, but is excessivelyconservative for a connection using web framing angles. However,when connections are SUbjected to axial as well as transverseloads, the method referred to above is excessively conservativefor both types of connections.

Research is needed to determine accurate procedures andcriteria for determining the web or plate thickness required tomatch fillet weld strength. The parameters to be studiedinclude loads ranging from pure shear to pure axial, coped anduncoped beams, length of connections ranging from 5 1/2 in. to 291/2 in. and various clip and angle leg sizes. Testing of fUllsize components is required. An analytical counterpart may alsobe desirable.


RECOMMENDATION BII: COMPOSITE COLUMNS

ANALYTICAL AND EXPERIMENTAL STUDIES SHOULDBE CONDUCTED TO DEVELOP IMPROVED DESIGNPROVISIONS FOR COMPOSITE COLUMNS.

There is a lack of up-to-date information on the strength ofcomposite columns. Existing test data were Obtained fromlaboratory specimens. Design rules included in the LRFDspecification are an extension of the structural StabilityResearch Council studies concerned with allowable stress design.These formulas may be unnecessarily conservative especially foreccentrically loaded columns.

Experimental studies should be conducted on full-scalecomposite columns. The tests should include the fOllowing range

19

of parameters: eccentricity ratio - 0 to 2; slenderness ratio 30 to 90; steel area - 5 to 20 percent. Analytical models shouldbe developed for predicting the ultimate strength behavior.

A three man-year level of effort is required.

RECOMMENDATION B12: COMPOSITE FLOOR SYSTEMS

A COMPREHENSIVE RESEARCH PROGRAM SHOULD BEUNDERTAKEN TO ESTABLISH STRENGTH CRITERIA FORCOMPOSITE BEAMS AND FLOOR SYSTEMS AND THEDEVELOPMENT OF INNOVATIVE SYSTEMS USING SUCHCONSTRUCTION.

Past research has provided the supporting data for thecurrent design provisions of the proposed LRFD Specification.These provisions govern the design of beam sections subjected topositive or negative bending. Work is needed to establish thestrength of continuous composite beam and floor systems includingthe effect of connections with partial rigidity and strength.Preliminary work is underway to investigate the moment-rotationbehavior and low-cost composite beam-column connections that relyon the floor reinforcing steel to resist the tension forcecreated by the moment.

The research program on composite construction shouldconsider the following: The effects of construction loads andservice loads on permanent deflections; models for predicting thedeflection behavior of partially composite systems; the behaviorof low cost beam-column connections for composite members; theuse of post-tensioned concrete slabs and/or steel beams.Applications to braced frames with composite floors andstructures with prefabricated composite units should be studied.

A multi year level of effort is required.

RECOMMENDATION B13: BAR JOIST SYSTEMS

EXPERIMENTS SHOULD BE CONDUCTED TO ESTABLISHSHEAR CAPACITY AND MINIMUM SIDE COVER INCOMPOSITE BAR JOIST SYSTEMS.

Economies can be obtained in bar joist construction if thefloor slab can be made to act compositely with the girdersupporting the bar joists by using shear studs on the girderflange. Information is not available on the performance of shearstuds in this condition with bar joists supported on the girderflange in the vicinity of the studs.

Pushout tests on stud assemblies and several full-scalegirder tests should be conducted to establish stud capacities and

20

side cover requirements for the studs.

A one-half man-year level of effort is required.

RECOMMENDATION B14: NEW STRUCTURAL MEMBERS

NEW STRUCTURAL SHAPES SHOULD BE DEVELOPED FORIMPROVING THE ECONOMY OF STEEL FRAME BUILDINGS.

The use of large built-up structural members for framingsystems is increasing. Economies could be achieved if largerrolled sections with higher moments of inertia were available.

Studies should be conducted to determine the feasibility ofproducing larger rolled structural shapes, identify the potentialmarket for these shapes and evaluate the savings in fabricationcosts.

A one-man year level of effort is required.

C. FRAMES

Considerable research has been carried out on the behaviorof individual structural elements and on plane frames of small tomoderate size. There is also a large body of informationavailable on the behavior of connections, floor systems,partitions, and cladding - elements that affect the loading onframes and their resistance. As indicated by recommendations inother sections of this report, much additional research is neededon all of these elements. But there is a primary need forresearch directed towards correlating and integrating theseinfluences. Improved understanding of the three dimensionalbehavior of total building systems involving more realisticassessment of strength, stability, and stiffness is required toreduce costs of steel buildings. The recommendations of thissection are intended in various ways to support the attainment ofthis basic objective.

RECOMMENDATION Cl: THREE DIMENSIONAL BEHAVIOR

ANALYTICAL AND EXPERIMENTAL STUDIES SHOULD BECONDUCTED ON THE THREE DIMENSIONAL BEHAVIOR OFSTEEL FRAMES.

The response of bare steel frames to given loads has been,and will probably remain, the basis for the development of designequations. This response - the stiffness and strength of theba r e frame - is aff ected by a number of th ing s: imper f ect ions,residual stresses, material nonlinearities, loading history,large deflections, post-buckling strength, and connection

21

behaviore

Analytical and experimental studies are needed to improvethe presently inadequate level of understanding of bare framebehavior. Realistic analytical modeling of three dimensionalframes that includes these effects is needed. Parallellaboratory testing of three dimensional subassemblages and smallbuildings should be conducted to provide information needed tocalibrate or to confirm these models. The physical researchshould be on mUltistory frames - of the order of three to eightstories - and should include both service load and ultimate loadbehavior.


RECOMMENDATION C2: INFLUENCE OF CONNECTIONS

ANALYTICAL AND EXPERIMENTAL STUDIES SHOULD BECONDUCTED TO EVALUATE THE INFLUENCE OF SEMI-RIGIDCONNECTIONS ON THE BEHAVIOR OF STEEL FRAMES.

Connection behavior, the most important factor influencingbare frame behavior, requires special attention. It is thesubject of several other recommendations in this report, e,g.,BS, B6, and DI. A separate topic should be the influence ofconnections on frame behavior - as distinct from studies of thecharacteristics of connections as individual elements. Ofparticular concern is the influence of partially rigidconnections. This research should include an evaluation of theavailable analytical models and experimental data on the momentrotation characteristics of semi-rigid connections. Existingcomputer programs for including connection flexibility should bestudied, evaluated, and extended. Further research should beconducted on the influence of connection rigidity on columnstability. A major effort should be made to extend this researchinto the determination of the influence of connection rigidity onoverall, three dimensional frame behavior. This should berelated to the analytical and experimental research called for inRECOMMENDATION CI.

A multi man-year effort is required.

RECOMMENDATION C3: CLADDING AND INFILLING

ANALYTICAL AND EXPERIMENTAL STUDIES SHOULD BECONDUCTED ON THE INFLUENCE OF FLOORS, PARTITIONS,AND CLADDING ON STIFFNESS AND STRENGTH.

It is well known that the various types of infilling controlthe ways in which loads are transmitted to the steel frame andthat they often interact structurally with the frame in resisting

22

these loads. Infilling can offer major - even dominant resistance to displacement at service loads and it can alsocontribute significantly to the ultimate resistance of the totalbuilding system. At present this influence is either ignored,accounted for by judgment, or calculated in some ad-hocapproximate way. Many studies have been made on the stiffnessand strength of different types of floors, partitions, andexterior cladding in direct tension and compression, flexure, andshear (racking and diaphragm action). Relatively littlequantitative research has been done on infilling-frameinteraction however.

There is a need to extend analytical models of the typecalled for in RECOMMENDATION CI to include the effect ofinfilling. Associated with this is the need to collect andcorrelate available quantitative information on the structuralcharacteristics of major types of infilling. Laboratory testingof three dimensional steel frames containing representativeinfill elements should be conducted for the purpose ofcalibrating or confirming analyses.


RECOMMENDATION C4: LATERAL DEFLECTION

ANALYTICAL NETHODS SHOULD BE DEVELOPED FORCALCULATING LATERAL DEFLECTIONS OF BUILDINGS.

Related to the previous three recommendations but having adifferent major thrust is the need to develop improved analyticalmethods for the calculations of lateral deflection under bothstatic (or quasi-static> and dynamic (wind and earthquake) loads.Experience has shown that the lateral deflection of low to mediumrise steel buildings sUbjected to wind loading is often far lessthan predicted by conventional analytical methods. Recentstudies suggest that the discrepancies between observed andcalculated drift are not due to the methods of assessing windloading but must be accounted for by structural actions.Conversely, some tall buildings have experienced undesirable,uncalculated lateral motion effects. Analytical methods thatinclude the features described in RECOMMENDATION Cl to C3 (threedimensional behavior and the influence of connections andinfilling) and realistic first and second order elastic staticand dynamic response characteristics are needed. These methodsshould be used in studies directed toward the establishment ofrealistic drift criteria or guidelines for wind loading andmoderate earthquake loading.


23

RECOMMENDATION C5: FIELD MEASUREMEN'!'S

FIELD MEASUREMENTS OF THE RESPONSE OF AC'l'UALBUILDINGS SHOULD BE MADE.

Most research is effectively conducted under the controlledconditions obtainable either in the laboratory or in analysis ofsystems of specified geometry, element properties, and supportconditions, under prescribed loading. Nevertheless, studies ofanalytical or physical models can never fUlly duplicate thebehavior of actual bUildings. Although field measurements ofbuilding response cannot be the primary basis for research, theyare essential for the purpose of calibrating, correcting, orexposing the imperfections of laboratory and analytical research.

Buildings in earthquake and hurricane regions have beeninstrumented, but additional efforts of this type are needed.They should be long range studies and they should b~ correlatedwith controlled environment (laboratory or analytical) research.The phenomena studied should include relative resistance of frameand infilling, frequencies, drift, twist, acceleration and otherfactors that influence the serviceability or strength of thetotal system.


RECOMMENDATION C6: COMPOSITE CONSTRUCTION

ANALYTICAL AND EXPERIMEN'!'AL STUDIES SHOULD BECONDUCTED TO ESTABLISH THE BEHAVIOR OF COMPOSITESTEEL-CONCRETE FRAMING SYSTEMS AND ELEKEN'l'S.

One of the most pronounced recent trends in tall buildingconstruction has been in the direction of using structural steeland reinforced concrete in combination as primary structuralelements. The composite tubular system has become increasinglypopular in the construction of tall buildings over the past fewyears. In this system the framed tube, consisting of closelyspaced reinforced concrete exterior columns and deep spandrelbeams made of reinforced concrete or structural steel, resistslateral loads produced by wind and/or earthquake. Structuralsteel framing supports the gravity loads. The steel floormembers are connected to small steel columns which are embeddedin the reinforced concrete exterior columns. The efficiency ofthis system is attributed to the advantageous use of the bestcharacteristics of both steel and concrete. The steel floorframing is light and, as a result, smaller interior steel columnsare needed. In addition, the light framing provides flexibilityfor space planning, particularly in the core. Above all, thesteel frame can be erected rapidly. The economy of the tubesystem with steel spandrels has been proven, and a few buildings

24

in Dallas and Houston, Texas have already been constructed withthis combination. In about 90 percent of the tube designs todate, reinforced concrete spandrels have been used mainly becauseof the uncertainties associated with the connection between asteel beam and a concrete column.

Research is needed on the overall performance of compositeframing systems in addition to work on individual compositeelements such as beams and columns. The three-dimensionalperformance of these systems, time-dependent changes instiffness, damping character is tics , and stiffness changes underdynamic loads require study. An experimental and analyticalparametric study is also needed to determine efficient means ofdeveloping the moment capacity of the steel spandrel beams at thesteel beam-concrete column joint and to determine the rigidity ofthe joint itself.


RECOMMENDATION C7: COLD-FORMED CONSTRUCTION

EXPERIMENTAL STUDIES SHOULD BE CONDUCTED TOESTABLISH THE BEHAVIOR OF MULTI-STORY FRAMINGSYSTEMS USING COLD-FORMED STEEL MEMBERS.

Cold-formed members are starting to be used for mUlti-storybuildings up to five stories. Such construction offersopportunities for innovative design concepts includingnmonocoquen construction, improvements in incorporatingarchitectural and mechanical elements with the structural system,and more effective use of material and improved structuralefficiency resulting from the ability to control the shapes ofmembers.

Analyti.cal and exper imental research is needed to addressaspects of the following problems unique to cold-formed membersin building frames: local and overall stability of members,connections inc 1uding adhes i ve bonding, diaphragm act ion,composite construction using mixed materials (wood-metal, fiberreinforced materials - metal, etc.> and prefabricated assemblies.


RECOMMENDATION C8: NON-COMPACT SECTIONS

RESEARCH SHOULD BE CONDUCTED TO DETERMINE IFMOMENT REDISTRIBUTION CAN BE UTILIZED TOADVANTAGE IN FRAMES COMPOSED OF NON-COMPACTSECTIONS.

A large percentage of low-rise steel construction utilizes

25

non-compact members in the framing systems. Significant costsavings could be achieved if the principles of momentredistribution commonly used in plastic design could be appliedto such structures.

The following research is needed:

o Study of analysis methods to determine failure mechanismsin typical low-rise frames composed of non-compactsections.

o Comparison of frames designed using moment redistributionwith frames using elastic analysis.

o Full-scale tests of frames designed using momentredistribution to confirm procedures.


D. SEISMIC DESIGN

Approximately three-fourths of the annual constructioninvestment in the United States is in some 40 states that haveexperienced moderate or major earthquakes in the past. Seismicdesign is obviously an important consideration for steelbuildings. Earthquake related research has been conducted onsteel structures. Additional work is needed to estblish thebehavior of connections and individual members and theperformance of structural systems subject to large inelasticcyclic deformations of the type produced by earthquake loading.

RECOMMENDATION Dl: BEHAVIOR OF SEMI-RIGIDCONNECTIONS

AN EXPERIMENTAL AND ANALYTICAL RESEARCH PROGRAMSHOULD BE UNDERTAKEN TO EVALUATE THE INELASTICCYCLIC PERFORMANCE OF SEMI-RIGID BUILDINGCONNECTIONS.

Studies are needed to quantify the cyclic hystereticbehavior of semi-rigid beam-to-column connections in buildingstructures designed for conditions of low to moderate earthquakeloadings. Specific topics of needed research include:

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o Cyclic tests of various types of semi-rigid connections(end plates, cap and seat angles) to determine theirmode(s} of distress (local instability, fatigue)"and to quantify their moment-rotation response andhysteretic energy absorption capability under repeateddisplacement excursions.

o Develop analytical models to predict the non-linearresponse of connections of varying stiffness, andgenerate computer programs to assess the inelasticcyclic response, including resistance to incrementalcollapse, of a complete building system.

o Determine efficacy of available low cycle fatiguerelationships and cumulative damage models to predictthe cumulative effect of seismically induced inelasticdisplacement excursions on the connections.


RECOMMENDATION D2: DRIPT CONTROL CRITERIA

STUDIES SHOULD BE UNDERTAKEN TO CORRELATESERVICE LOAD WIND DRIPT CONTROL CRITERIAWITH LATERAL DISPLACEMENT PERFORMANCE UNDEREARTHQUAKE LOAD HISTORIES POR PLEXIBLYCONNECTED BUILDING PRAMES DESIGNED INREGIONS OP LOW TO MODERATE SEISMICITY.

Flexibly-connected (AISC Type 2) frames are common in lowrise building structures designed primarily for drift controlfrom wind at service loads. Research is needed to evaluate theirinelastic lateral displacement behavior under seismically inducedground motions. Studies are required in the following areas:

o Develop a rational method for calculating lateraldisplacements (wind drift) at service loads inType 2 building structures, including thecontribution of cladding and other non-structuralelements to overall frame behavior (see RECOMMENDATIONC2 and C4).

o Develop analytical models to assess the inelasticcyclic lateral displacement performance (inCludingconsideration of frame instability and incrementalcollapse) of flexibly-connected frames underearthquake load histories.

o Formulate design guidelines for flexibly-connectedbuilding frames (including connection strength andductility requirements, panel zone shear deformationlimits, bracing requirements, etc.) to ensure adequatedrift'control at service loads, and to satisfy

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ductility, strength, and stability demands forextreme loads during a seismic event.


RECOMMENDATION D3: SEISMIC PERFORMANCE

A RESEARCH PROJECT SHOULD BE UNDERTAKEN TOSUMMARIZE EXISTING PERFORMANCE DATA FORSTEEL BUILDINGS SUBJECTED TO SIGNIFICANTEARTHQUAKES.

Steel buildings which were not designed in accordance withtoday's seismic design criteria have survived significantearthquakes sustaining little or minor damage. Examples ofearthquakes where steel buildings survived and data are availableinclude San Francisco, Caracas, Mexico City, Managua, Guatamalaand several Japanese cities. The design profession and codewriters do not have the resources to evaluate past performancebecause documentation is scattered. The work should include:

o Review reconnaissance reports and identify typesof steel building construction and relative damage.

o Compare types of construction with current seismicdesign procedures and determine if the structures werein general conformance with code philosophy. If not,identify reasons for lack of expected damage.

o Identify information that can be readily used forcode development and design.

o Analyze past performance of various constructionsystems and review the need for fully ductilesystems.


RECOMIIENDATION D4: STEEL STUD WALLS

A COMPREHENSIVE RESEARCH PROGRAM SHOULD BEUNDERTAKEN TO DETERMINE THE ALLOWABLE SHEARRESISTANCE OF WALL SHEETING MATERIALS COMMONLYUSED WITH COLD FORMED STEEL STUD WALLS.

Load-bearing steel stud wall systems are commonly designedfor lateral force resistance using flat strap acting as in-planebracing. Limited work has been done to determine the allowableshear force resistance provided by sheeting material such aswallboard, lath and plaster and plywood.

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Past research has provided limited data for use with lathand plaster, plywood and wallboard shear walls. No work has beendone to evaluate the effectiveness of the bracing systems used inconjunction with these common sheeting materials. An advantageof steel studs in building construction is their non-combustibleclassification. However, only plaster or wallboard materialsare currently used in these non-combustible classifications sinceplywood is combustible. Unfortunately, plaster and wallboardhave relatively low shear resistance. other options need to beinvestigated. The following work is needed:

o Develop a wide range of shear values for commonsheeting materials by studying the effects ofvarying attachment spacing, steel stud basemetal gage and various anchorage details.

o Develop a methodology for calculating theallowable shear value for untested materials.

o Study the effects of combining the braced frameand wall sheeting materials.

o Investigate anchorage details and their impacton allowable loads.

o Develop new non-combustible shear resistingsystems such as steel sheet shear walls usingtension field action.


RECOMMENDATION D5: BEAM-COLUMN JOINTS

AN INTEGRATED EXPERIMENTAL AND ANALYTICALRESEARCH PROGRAM SHOULD BE UNDERTAKEN TOCLARIFY CYCLIC BEHAVIOR AND RELIABILITY OFBEAM-COLUMN JOINTS HAVING BEAM-TO-COLUMNFLANGE CONNECTIONS AS WELL AS THOSE ATTACHEDTO A WEAK COLUMN AXIS.

Moment-Resistant Frames are predominant in seismic designof steel frames. In addition to their conventional use, they arealso employed in the perimeter framing of tall buildings. Thecritical element in such framing is the joint, Le., the entireassemblage at the intersection of members. The connectionconsisting of those elements that connect the member to thejoint, which may be affected by the behavior of the entire joint,is usually the most critical element of the assemblage. In spiteof the wide use of such joints, the seismic design criteria arepoorly defined, and there is a considerable degree of uncertaintyregarding their capacity. Very limited research information isavailable on the cyclic behavior of joints of realistic size.Due to competitive pressures, inadequate designs are sometimes

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accepted even for new frames. There is no real consensus, and itis essential to clarify for the designers the proper bounds.


o Carry out analytical studies for the design ofexperiments to simulate the relevant size rangeof beam-column connections. This study should besupplemented with inelastic dynamic frame analysesto determine the bounds on joint loadings.

o Design and carry out two-dimensional experimentson joints of realistic sizes (approximatelyhalf-size and larger) for connections of twotypes:

a. Beam-to-column flange connectionsb. Beam-to-column web connections

For either type, the all-welded as well as connectionswith bolted web and welded flanges should bestudied. The possibility of reinforcing boltedwebs with welding to inhibit bolt slip should beexplored.

o Extend the the two-dimensional studies tothree dimensions.

o Formulate practical rules for sizing panel zones,stiffeners (continuity plates), as well as flangeand web connections.


RECOMMENDATION D6: BEAM-COLUMNS

A COMPREHENSIVE RESEARCH PROGRAM INVOLVINGEXPERIMENTAL AND THEORETICAL STUDIES SHOULDBE UNDERTAKEN IN ORDER TO GAIN REALISTICKNOWLEDGE OF THE CYCLIC INELASTIC BEHAVIOROF BEAM-COLUMNS.

Although it would not be desirable to design beam-columnsfor inelastic cyclic buckling, analytical tools are needed torepresent their behavior when studying inelastic dynamic responseof structures SUbjected to severe earthquake motions. In bracedframes with relatively heavy bracing members the columns may beSUbjected to large cyclic axial forces and moments which may leadto overall structural instability. The research work to date onbeam-column behavior has been almost exclusively devoted tounidirectional loading. In the absence of data on the cyclicbehavior of beam-columns, a few attempts have been made toformulate simple models derived from the knowledge of behavior ofbeams and bracing members.

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The research should involve the following:

o Effect of end conditions.

o Effect of strength and stiffness of columns incomparison to that of beams.

o Loading history to include ratio of end moments aswell as their magnitudes relative to axial force.

o Effect of geometrical properties.

o Experimental work should include small scale andfull scale members, as well as subassemblages andprototypes.

o Analytical work should be aimed at development ofrealistic and practical hysteresis models foranalysis purposes, as well as development ofdesign criteria to alleviate structural instability.

A three to five man-year level of effort is required.

RECOMMENDATION D7: TUBULAR MEMBERS

A COMPREHENSIVE RESEARCH PROGRAM INVOLVINGEXPERIMENTAL AND THEORETICAL STUDIES SHOULDBE UNDERTAKEN IN ORDER TO EVALUATE THEDUCTILITIY AND ENERGY DISSIPATION CAPACITYOF STEEL TUBULAR MEMBERS SUBJECTED TO LARGECYCLIC DEFORMATIONS.

Cold formed rectangular steel tubes have gained popUlarityin recent years especially as bracing members in mUltistoryframes. Lighter structures utilize these shapes for columns andbeams as well. In a few past studies it has become quite clearthat under cyclic loading severe cross section deformation inregions of plastic hinges leads to local buckling and prematurefailures. Concrete filling is one way to delay this mode offailure. The concrete inside the tubes prevents severe localbuckling of steel tubes while the tube itself gives excellentconfinement to concrete. Some preliminary work has produced verypromising results. Research is needed to study the hysteresisbehavior and modes of failure under different cyclic loadconditions. Theoretical procedures should be developed tosynthesize the hysteresis models and establish design criteriafor such composite members.

The research should involve the following:

o Effect of confinement via relationship between thearea or volume of steel and concrete.

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o Effect of bond between steel tube and concrete.

o Effect of relative strength of steel and concrete.Normal strength, high strength and light weightconcrete should be included.

o Effect of width-thickness ratio of tube walls.

o Effect of different loading histories.

o Experimental work should involve:a. Reduced scale as well as full scale specimensb. Beams, columns, and bracing membersc. Connectionsd. Subassemblages and prototypes

o Development of analysis techniques and design criteria.


RECOMMENDATION DB: END-PLATE BEAM-TO-COLUMNCONNECTIONS

DESIGN CRITERIA AND PROCEDURES SHOULD BE DEVELOPEDFOR END-PLATE MOMENT CONNECTIONS SUBJECTED TOEARTHQUAKE MOTIONS.

In recent years, considerable experimental and analyticalresearch has been conducted on the behavior of end-plate momentconnections under static loading. Some limited work has beendone in Italy and New Zealand on the behavior of moment end-plateconnections under cyclic loading; however, design rules have notbeen formulated. Still these connections are being used inbuildings located in moderate to severe earthquake~reas. Thus,there is need for a comprehensive study of the cyclic behavior ofend-plate connections for safety reasons.

Research is needed on the cyclic behavior of moderate tolarge capacity, 4- and a-bolt, extended configurations as used inmUlti-story frames. End-plate thicknesses for these connectionsare typically between 3/4 in. and 2 in. and corresponding boltdiameters are between 3/4 in. and 1-1/2 in. The experimentalwork should consist of sUbjecting fUll-scale, end-plate connectedbeam and column assemblies to severe cyclic loading. The loadingmust simulate the effects of strong earthquakes. Majorparameters of the study should be end-plate geometry, grade ofsteel, bolt diameter and bolt type, and the random nature ofearthquake cyclic effects. Analytical studies should include thedevelopment of a finite element model and associated coding topredict the connection behavior. The finite element model mustaccount for the effects of nonlinear material properties andpossible plate separations at the end-plate/column flangeinterface. Portions of both the beam and column must be modeled.

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RECOMMENDATION D9: BOLTED WEB MOMENT CONNECTIONS

LOW CYCLE FATIGUE LIFE OF BEAM-TO-COLUMN MOMENTCONNECTIONS MUST BE INVESTIGATED TO PROVIDE ARELIABLE BASIS FOR SEISMIC DESIGN.

In seismic design of ductile moment resisting frames, beamto-column moment connections must be capable of developing thefull plastic capacity of the beam section unless it can be shownthat adequate ductility is provided by a lesser connection. Forreasons of economy, it is common practice to use fUll-penetrationf lange welds and fr iction-type bol ted web connect ions. Due toslippage of the bolted web connections under a combination ofhigh moment and shear, the beam flanges must develop the plasticmoment capacity of the section at the beam-to-column connection.While welded-flange, bolted-web connections have been found toexhibit considerable ductility, their low-cycle fatigue lifeunder large inelastic deformations is not as good as that foundfor fUlly welded connections. In a strong motion earthquake,even a symmetrical structural system is likely to behaveunsymmetrically. In reality, then, the welded-flange connectionswill be subjected to out-of-plane bending and torsion. The lowcycle fatigue life of the beam-to-column connections will beinfluenced by the additional stresses. For a reliable predictionof the three-dimensional behavior of real bUildings, thehysteretic behavior of moment connections under three-dimensionaldeformations must be known. Since such predictions must becarried out by computer, a reliable analytical model ofconnection behavior is necessary.

The proposed study would have a comprehensive experimentalprogram and qn analytical counterpart. The experimental workwould require testing of a variety of connection configurations,under several three-dimensional load histories. Theconfigurations should represent a range of member sizes and theloads should simulate the inelastic three-dimensional response ofa real building under a strong motion earthquake. Thedevelopment of an analytical model for the representation ofconnection behavior should be carried out in conjunction with theexperimental program. The analytical model should capture thedominant behavior of this type of connection under extreme cyclicdeformations. When implemented in a computer program, the modelshould permit a reliable assessment of the behavior of a complexstructure including its resistance to incremental collapse.

A three to four man-year level of effort is required.

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RECOMMENDATION DIO: BRACING CONNECTIONS

ANALYTICAL AND EXPERIMENTAL STUDIES SHOULDBE UNDERTAKEN TO ESTABLISH THE PERFORMANCEOF GUSSETED BRACING CONNECTIONS.

Diagonal bracing provides an efficient means of resistinglateral loads both in tension and compression. The ability ofthese members to yield and buckle in a controlled manner providessubstantial increased energy absorption to the structural system.Much work is needed to understand the fundamental behavior andmodes of failure of gusseted bracing connections and theirinfluence on the response of the bracing and total structuralsystem.

The research should include:

o Single diagonal and X-braced diagonal configurationswith various structural shapes, such as single angles,double angles, channel sections, rectangular tubes,circular tubes (pipes), and wide flange sections.

o In-plane and out-of-plane buckling behavior shouldbe studied to determine the connection detaildifferences and bracing behavioral differencesfor these systems.

o Both concentric and eccentric brace connectiondetails should be inCluded in this program.

o Gusset plate connections should include theappropriate attachments to the associated beamsand columns as well as to the braces. Welded andbolted connection details are needed.

o Experimental studies at full and reduced scalesshould be conducted to establish reliable datafor the development of design recommendations.

o Theoretical and analytical studies to explore thedominant behavioral characteristics of gusset plateconnected bracing members should be conducted inconcert with the experimental studies.

o Design procedures, recommendations, and specificationsshould be developed to ensure satisfactory performanceof the connections under severe earthquake groundmotions.

A four man-year level of effort is required.

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RECOMMENDATION D11: VISCOELASTIC DAMPING

A RESEARCH PROGRAM IS NEEDED WHICH (1) WILLDESCRIBE AND DOCUMENT THE RELATIONSHIPS BETWEENVISCOELASTIC MATERIAL PROPERTIES AND DAMPINGPROVIDED BY RECBANICAL SYSTERS, (2) WILLPERFORM EXPERIRENTAL STUDIES TO ESTABLISHAND VERIFY APPROPRIATE ANALYTICAL ALGORITBRSFOR STRUCTURAL DESIGN AND ANALYSIS, AND (3)WILL DERONSTRATE THROUGH 'l'YPICAL STRUCTURALCASE STUDIES THE EFFECTIVENESS OF MECHANICALVISCOELASTIC DAMPING SYSTERS FOR EARTHQUAKERESISTANT DESIGN.

Mechanical damping systems can dissipate significant amountsof energy during vibratory motions. It is well known thatstructures sUbjected to severe earthquake ground motions mustdissipate some of the input earthquake energy through nonlinearmaterial damping. By adding mechanical viscoelastic damping itis possible to reduce the structural vibrations caused byearthquakes and the amount of structural and nonstructuraldamage.


o Develop mechanical damping systems which utilizeviscoelastic materials for energy absorption.These can be of the direct shear type, rotary sheartype, or other.

o Experimentally determine the characteristics of fullsize mechanical viscoelastic damping systems.

o Establish appropriate analytical algorithms for thesedamping systems. The analytical algorithms would beused for design purposes and analytical verificationsof the dynamic response characteristics of completebuilding systems.

o Conduct a parameter study to determine the optimumamount of mechanical damping to be added to variousstructural systems in order to minimize economicallythe earthquake hazard for these systems.

o Develop recommended procedures for the design ofmechanical damping systems considering ease ofapplication by the design profession.

o Extend the results to retrofit of existing buildingsand design for strong winds.


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RECOMMENDATION D12: DUCTILITY DEMAND

RESEARCH SHOULD BE CONDUCTED TO QUANTIFYDUCTILITY DEMANDS AND CAPACITIES FORSTRUCTURAL SYSTEMS, ELEMENTS AND CONNECTIONSAND DEVELOP CRITERIA FOR PERFORMANCEASSESSMENT.

Deterioration in strength of elements of steel structures isoften a consequence of localized failures, such as crackpropagation and fracture at connections, or localizedinstabilities (local and lateral torsional buckling) withinmembers. The deterioration caused by these localized failures isa function of the number and magnitudes of inelastic excursions.The profession and code writing bodies need information thatpermits a quantitative assessment of seismic performance in orderto develop acceptable detailing criteria. Consideration must begiven to the randomness of seismic input and the cumulativeeffects of inelastic excursions on structural damage. Cumulativedamage models, of the type used extensively in mechanicalengineering, can provide much of the needed information.


o Evaluation of the number and magnitudes of inelasticexcursions a structure or structural element isexpected to experience in an earthquake.

o Development of cumulative damage models forstructural elements based on low-cycle fatigueconcepts.

o Conduct laboratory tests to validate damage models.

o Development of representative cyclic loading historiesfor testing, so that test results can be generalized todamage prediction under random loading histories.


RECOMMENDATION D13: BRACED FRAME STABILITY

ANALYTICAL AND EXPERIMENTAL STUDIES SHOULD BECONDUCTED TO DETERMINE THE STABILITY OF BUILDINGSYSTEMS WITH THE LATERAL FORCE RESISTANCE PROVIDEDBY K OR CHEVRON BRACING.

One of the basic concepts of seismic design is that if thebuilding system is designed to respond in an inelastic manner toground shaking having an intensity much larger than the yieldlevel of the structures, the structure should yield withoutundergoing collapse. Building systems using K or Chevron bracing

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for lateral resistance of seismic forces and movements frequentlyhave been used in areas of high probability of strong seismicshaking. In the K braced system, the column to which the apex ofthe brace is connected continuously supports vertical dead andlive loads. If the compression segment of the brace were tobuckle, the column would have additional forces induced by theremaining brace segment which are not usually accounted for indesign. Similarly, the Chevron brace would induce forces intothe horizontal flexural member which are not usually consideredin design.

Analytical and exper imental work should determine theinelastic behavior of these bracing systems and appropriatedesign cr iter ia shou ld be estab I ished to provide adequatestability during large intensity earthquakes.


RECOMMEImATION D14: LATERAL BRACING

AN EXPERIMENTAL STUDY SHOULD BE CONDUCTEDTO DETERMINE LATERAL SUPPORT REQUIREMENTSFOR MEMBERS SUBJECT TO SIGNIFICANT INELASTICRESPONSE DORING EARTHQUAKES.

There have been numerous tests of subassemblages composed ofsteel beams and columns. In almost all cases the lateralsupports of the members tested were not under study. Thus thelateral supports provided were essentially rigid and closertogether than needed. Over the years there have been manystudies to determine the spacing of lateral support members.These tests, however, do not provide the information needed toevaluate the requirements for lateral bracing properly formembers undergoing the potentially large inelastic deformationsrequired for members in areas of high seismicity.

New experimental research should be conducted to determinethe design requirements for members of seismic frames havingreversing, high moment gradients and non-linear responsecharacteristics. The tests should also consider the lateralsupport offered by a composite floor slab. A variety of bracingconfigurations should be studied.


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RECOMMENDATION D15: OVERALL SYSTEM RESPONSE

AN INTEGRATED ANALYTICAL RESEARCH PROGRAM SHOULDBE UNDERTAKEN TO DETERMINE THE THREE-DIMENSIONALEFFECTS IN THE NONLINEAR RANGE OF ARCHITECTURALAND STRUCTURAL CHARACTERISTICS OF IRREGULARBUILDINGS IN ORDER TO DETERMINE THEIR CAPACITYTO RESIST EARTHQUAKES OF VARYING LEVELS OFSEVERITY.

Architects are becoming conscious of the importance ofincluding earthquake resistance considerations in theirconceptual designs. Architectural concepts take advantage of theversatility of steel framed structures, and the use ofconfigurations involving setbacks, asymmetry, and combinations ofshear walls and moment frames is quite common. There is verylimited quantified information on strength and drift for varioustypes of building concepts. Architects as well as engineers needdata on bounds for irregUlarity, interaction of structural andnon-structural elements, and effects of mixed structural systems.Torsion, relative importance of shear walls and frames in thenonlinear range, and interaction of the structural frame withnon-structural elements, such as curtain walls, are effects thatare best investigated through three-dimensional models. Analysesthat utilize computer software for three-dimensional nonlinearanalyses can be very he lpfu 1 in determining dr ift and strengthcharacteristics of structures that cannot be reliably modeled intwo dimensions. An additional benefit of three-dimensionalanalyses is to establish limits on setbacks, asymmetry, etc.,within which two-dimensional modeling gives acceptable results.


o Documentation of architectural systems for low-risebuildings that incorporate features which requirethree-dimensional evaluation.

o Classification of structural systems into groupsthat are susceptible to analysis with existing software.

o Evaluation of structural systems for which new softwareor modified software needs development.

o Analysis of typical structures from each classificationto determine their response characteristics into thenonlinear range.

o Engineering investigations, utilizing the results ofanalysis, to establish bounds on drift and strengthrequirements fot categories of building concepts.

o Guideline documents that architects and engineerscan use for design.

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A five man-year level of effort is required.

RECOMMENDATION D16: EVALUATION OF EXISTING BUILDINGS

AN EXPERIMENTAL AND ANALYTICAL STUDY SHOULD BECONDUCTED TO ESTABLISH LEVELS OF SEISMIC RESISTANCEOF LOW-RISE STEEL FRAIIE BUILDINGS, AND PROCEDURESSHOULD BE DEVELOPED TO STRENGTHEN THEIl WHERENECESSARY TO ACCEPTABLE LEVELS.

Initial emphasis on retrofit and strengthening of existingbUildings has been on unreinforced masonry buildings. Whereas itwas originally felt that such buildings had to be demolished,recent experimental and analytical work showed that it waspossible to strengthen them and make them earthquake resistant.The economics of strengthening such buildings was a majorconsideration in this evaluation. Although low-rise structuralsteel buildings are less susceptible to damage, their level ofearthquake resistance has not as yet been demonstrated throughexperiments and analysis. Dynamic analyses of buildings tocalculate their response to earthquake excitations is now aroutine procedure, but the emphasis has been on the analysis ofstructures that are being designed for new construction.It is necessary to investigate existing structures to find theirearthquake resistance capacity and to develop methods of retrofitto bring their resistance up to acceptable levels.

An extensive analytical and experimental program should becarried out to identify the seismic resistance capacity ofexisting steel structures of various typical configurations thathave not been designed to present seismic codes. Theexperimental work should consist of testing existing buildingsand laboratory experiments of framing that corresponds to thestructural systems of typical classes of existing buildings.Since existing buildings cannot be tested to destruction,information obtained from such tests must be supplemented bylaboratory tests to determine the capacity of major elements ofthe structures. Subsequently, concepts should be developed forstrengthening buildings found susceptible to damage at practicalseismic excitation levels. Criteria should then be developed foreconomic methods of strengthening and procedures should berecommended for analysis and design to meet these criteria.

A six man-year level of effort is required.

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E. LOAD AND RESISTANCE FACTOR DESIGN

The proposed AISC Load and Resistance Factor Design (LRFD)specification for structural steel buildings was released forreview and trial use in 1983. The LRFD specification is theprototype for a new generation of structural design codes.Research opportunities exist for facilitating and expeditingimplementation of the LRFD specification. They range fromassembly of existing data to laboratory testing to resolvespecific questions on topics where the new specification may beover ly conservati vee

RECOIUIENDATION E1: CONNECTIONS WITH OVERSIZEHOLES

AN ANALYTICAL STUDY SHOULD BE CONDUCTED TODETERMINE THE INFLUENCE OF SLIP IN BOLTEDCONNECTIONS ON FRAME GEOMETRY AND FRAMESTABILITY.

The slip critical high-strength bolted joints are designedin LRFD at service loads and the nominal specified shear strengthis the same qS the allowable shear for such bolts in ASD. Thus,slip may occur at overloads. Is slip at overloads astrength/safetyproblem in such joints when built with oversizedholes? The question arises in bracing connections in high risebuildings. It has been suggested that slip at overloads coulddistort the frame to such a degree that instability may occur.

Research along two lines of attack is needed: First,considering the random alignment of holes, how much slip willrealistically occur in a multifastener joint? A reexamination ofthe existing test data is needed to assure that this problem ishandled adequately in the specifications. Second, an analyticalstudy is needed on the influence of slip in bolted connectionswith oversize holes on frame geometry to determine whether frameinstability problems could result. The type and size of buildingsfor which higher bolt design values can be used in slip-criticalconnections should be determined.


RECOIUIENDATION E2: WEB CRIPPLING

EXPERIMENTAL STUDIES SHOULD BE CONDUCTED TOEVALUATE WEB CRIPPLING BEHAVIOR OF LIGHTBEAll SECTIONS WITH SEATED CONNECTIONS.

The proposed LRFD formula for web crippling at bearing endsof beams (i.e., seated connections or wall bear ing beams) mayseriously affect the use of seated connections. The web

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crippling capacity of some of the lighter sections (WI4x22,W12x14, WIOxI2) will be reduced well below the equivalent ASDcapacity.

The LRFD specification requires that lateral support beprovided at bearing ends. The present AISC manual infers thatside clips or top clips must be used with seated connections.For the lighter sections, a typical side clip will not onlyprovide the required lateral support but also will providesignificant vertical load reaction capacity.

Tests should be conducted for the lighter beam sections toevaluate the contribution of the side and or top clip to webstability (see also RECOMMENDATIONS B3 and B4).


RECOIUIENDATION E3: TECHNOLOGY TRANSFER

TEACHING MATERIALS AND DESIGN AIDS SHOULDBE PREPARED TO ACQUAINT BUILDING OFFICIALSWITH THE USE OF LRPD.

Rapid acceptance and use of LRFD is contingent upon buildingofficials having a thorough understanding of the principles anddetails of this new design procedure.

Educational material should be prepared to teach the use ofLRFD to building officials. It should include any specialinformation or design aids needed by building departments toreview and check LRFD designs. Video cassette type lectures andthe establ ishment of a point of contact to respond to questionson details of the specification should be considered. Materialshould be prepared for administrative level officials and planexaminers.

A one-fourth man-year level of effort is required.

RECOIUtEImATION E4: RESISTANCE FACTORS

A SYSTEMATIC STUDY SHOULD BE UNDERTAKEN TOCOLLECT INFORMATION ON ACTUAL PRODUCTS ANDSTRUCTURES FOR USE IN COMPUTING RESISTANCEFACTORS FOR STRUCTURAL MEMBERS.

Data have been collected on the variation of geometrical andmechanical properties of steel members. Asystematic assembly ofthese data for the broad range of steel products and fabr icatedstructural elements has not been reported. Higher ¢ factorscould be used for those cases where higher mean values or smallercoefficients of variation than presently used are obtained.

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o Systematic collection of data on the variations inthe geometric properties of the major rolled shapes,tubes, fabricated sections, bolts and welds.

o Systematic collection of data on the variations inthe mechanical properties of rolled shapes, plates,cold-formed and hot-rolled tubes, bolts, weldingelectrodes, and welds.

o Systematic collection of data on as-built imperfections,such as out-of-plumb, sweep, camber, etc., as a functionof quality control. .

o The calculation of ¢ based on the above data base forthe various products and class of members and/orstructures.


RECOMMENDATION E5: SERVICEABILITY CRITERIA

RESEARCH SHOULD BE UNDERTAKEN TO DEVELOP THEDATA BASE AND ANALYSIS PROCEDURES NEEDED TOPREPARE RATIONAL AND PRACTICAL SERVICEABILITYCHECKING PROCEDURES FOR LRFD.

The use of the computer as a design tool and modernarchitectural requirements have led to building systems that areflexible and lightly damped. Since structural stiffness hasremained the same or declined as strength has increased, modernbuildings and building systems are increasingly susceptible toobjectionable static or dynamic structural movement. Presentcodes and standards offer little guidance on these problems.Ser v iceabi I i ty is more an economic than safety issue, andserviceability requirements are negotiable between engineer,architect and building owner. Serviceability criteria need to beflexible and adaptable to different building use requirements.However, the present lack of any meaningful criteria may beinterpreted by some to mean that serviceability is not important,which raises questions of professional responsibility. With themove to limit states design, serviceability will become anincreasingly important and delicate regulatory and designproblem.

The following research should be conducted:

o Serviceability limit states should be identifiedthrough surveys of building owners and occupants,and correlated with measurements of structuralloading and response. Serviceability limitsshould be related to occupancy.

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o Dynamic properties of structural systems must beidentified through a program to measure in situstatic and dynamic structural response.

o Load combinations should be developed for checkingdeflections under static loads against tolerablelimits.

o Simple serviceability checks must be developed tocontrol objectionable structural motions, takinginto account the load levels, the dynamiccharacteristics of the load, and the structuralresponse.


RECOMMENDATION E6: LATERAL MOTION CRITERIA

LIMIT STATE CRITERIA SHOULD BE DEFINED FOR THELATERAL MOTION OF BUILDINGS AND PERFORMANCECRITERIA DEFINED.

Drift or lateral motion of buildings is an important designconsideration. These criteria become a controlling factor forbui ldings greater than two to three stor ies. In the absence ofwind tunnel tests, arbitrary limits are imposed for this drift indesign. There is no information available to substantiate these1 imi ts. In many cases, these 1 imi ts resul t in an economicdisadvantage for steel structures.

Research should be conducted to define drift valuesassociated with the following 1 imi t states: internal partitionfailure, elevator tolerances, human comfort and building craneoperation.

A two man-year effort for three years is required.

RECOMMENDATION E1: VIBRATION CONTROL FOR LIGHTFLOOR SYSTEMS

TECHNIQUES ARE NEEDED TO INCREASE THE DAMPING INFLOOR SYSTEMS WHICH WILL ALLOW REDUCTION INWEIGHT WITHOUT ADVERSELY AFFECTING THEACCEPTABILITY OF THE FLOOR WITH REGARD TOANNOYING, OCCUPANT-INDUCED FLOOR VIBRATIONS.

If the weight of steel beam- or steel joist-concrete slabfloor systems is reduced, the savings in building costs can besignificant due to the pyramiding effects of beam, column, andfooting sizes. The obvious maximum effects on weight reductionare to decrease the concrete slab thickness, reduce the unit

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weight of the concrete or substitute a lighter material. Theresulting reduction in mass will, however, have an adverse effecton the vibration characteristics of the floor system. Sincedamping is the most important vibration parameter for floorsystems excited by normal office or residential human occupancy,the acceptability of an ultra-light floor system can be improvedby increasing the system damping.

Research is needed on methods and/or mater ials that can beused to increase the damping in floor systems. The problem isdifficult because of the extremely small amplitudes (0.030 to0.050 in.> that are perceived by humans to be annoying. Fullscale floor systems would have to be used in the research andparticular attention paid to the economics of the dampingmaterials selected, as well as the cost of the installationtechnique. Pilot applications in existing buildings will also beneeded.


RECOMKBRDATION B8: PLASTIC DBSIGN

STUDIBS SHOULD BE UNDBRTAKBN TO DETERMINEIF THE LRFD SPBCIFICATION CONTAINS ADBQUATEPROVISION FOR THB USE OF PLASTIC DESIGN.

The LRFD Specification rules for plastic design have beenincorporated as an integral part of the overall design provisionsrather than presented in a section of their own. As a result,plastic design using LRFD is not as readily apparent as with the1978 and earlier AISC Specifications.

A study is needed to develop guidance for plastic designusing LRFD. The results should be presented in a series ofpapers illustrating the use of plastic design concepts with theLRFD provisions.

A one-quarter man-year level of effort is required.

RECOMMERDATION E9: SYSTEM RELIABILITY

RESEARCH SHOULD BB UNDERTAKBN TO DBVELOP THBANALYSIS PROCEDURES AND DATA NEEDED TO TAKEADVANTAGE OF SYSTEM BEHAVIOR IN LRFD.

Development of LRFD and supporting reliability analyses havefocused on behavioral models andstatist~cs for individualmembers. While these behavior models are believed to berealistic for describing response of individual members underdesign loads, they ignore the fact that such members are integralto a system, the behavior of which under extreme loads is

44

complex. In certain highly redundant structures the systemreliability is considerably higher than that of any individualmember1 in other systems, the system reliability may be less.Since one of the ultimate goals of LRFD is more uniformreliability for all structures, it is plain that systems effectsshould be considered in some way.


o Establish realistic limit states for systems interms of the member limit states which areknown.

o Develop and validate procedures for computingsystem reliability.

o Develop criteria to take systems effects intoaccount in design through the use of partialfactors or other simple devices to reflect themode and consequence of system failure.


RECOIUIENDATION EI0: WIND AND SEISMICEFFECTS

RESEARCH SHOULD BE CONDUCTED TO ESTABLISH ARATIONAL AND CONSISTENT BASIS FOR WIND ANDSEISMIC EFFECTS IN LRFD.

The application of LRFD to buildings sUbjected to wind andseismic effects has not been thoroughly considered. Inconsidering wind effects, wind directionality and structuralenveloping have been taken into account only in an approximatefashion. The seismic analyses consider the ability of thestructural system to dissipate energy through inelastic cyclicdeformation in a rudimentary way. Moreover, unlike the limitstates for gravity loads, the limit state for seismic effectsconsists of some poorly defined deformation limit. The presentstatic-for-dynamic reliability analyses indicate lowerreliabilities for wind and seismic effects than for other loads.Research data presently are insufficient to determine whetherthese discrepancies are real or only apparent, and they could notbe resolved in developing the current LRFD specification.


o Identify appropriate limit states for earthquakes.

o Develop reliability analyses that take into accounttime-dependent nonlinear behavior explicitly.

4S

o Examine wind-directionality effects on thereliability of wind-sensitive structures.

o Develop equivalent lateral force requirements andperformance requirements.

o Coordinate LRFD with wind and earthquake engineeringcommunities.


RECOMMENDATION Ell: EXISTING BUILDINGS

RESEARCH SHOULD BE CONDUCTED TO EXTEND LRFDTO INCLUDE STRENGTHENING AND REHABILITATIONOF EXISTING STRUCTURES.

The proposed LRFD Specification was developed essentiallyfor the design of new buildings. For example, the materialcharacteristics used in the development of LRFD were· derived fromtests of current and recently replaced materials. However,everyday design practice requires the application ofspecification provisions to older structures for repairs,renovation etc. Research specifically directed to this problemwill extend the applicability of LRFD to this area of design.

The following work is needed:

o Development of a systematic method for evaluationof material properties of existing structures.Note that these properties are likely to be verydifferent from present day materials, and astatistically based sampling procedure may bedesirable.

o Development of methods of evaluating resistancefactors and reliability indices for structuralcomponents that were built by very differentconstruction methods as well as factors fordifferent classes of connections.

o Possible consideration of reduced life expectancyfor existing structures and evaluation of suchimplications on load factors and reliability.Consideration of the value of past performance of thebuilding on the LRFD evaluation.

o Formal application of the method to existing structuresthrough development of an applications manual orexample calculations.


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F. FIRE PROTECTION

Research opportunities exist for reducing the costs ofproviding fire protection for steel structures while maintainingcurrent levels of safety. The work would also provide a morerational basis for fire protective design. It includes thedevelopment of analytical design procedures, design aids, newfire protective materials and fire models for special structures.

RECOIUIENDATION FI: FIRE RESISTANT DESIGN

A COMPREHENSIVE ENGINEERING DESIGN PROCEDURESHOULD BE DEVELOPED FOR EVALUATING THE PERFORMANCEOF STEEL FRAME BUILDINGS UNDER FIRE EXPOSURECONDITIONS.

In many cases current design criteria based on arbitrarylimits such as the imposition of limits on steel temperature areoverly conservative. During the past two decades, ourunderstanding of fire phenomena and their impact on buildings hasincreased dramatically to the point where it is now possible todesign specific buildings for anticipated fire conditions in amanner analogous to current structural design. Unfortunately,the procedures and techniques for accomplishing an integratedfire resistant design are not readily available to the designcommuni ty. Per formance cr iter ia such as def 1 ection 1 imi ts andrequired strength conditions have not been developed. Currentfire resistance requirements also do not take into account theprobabilistic nature of fire occurrence in a manner comparable toother extreme loads such as earthquakes and extreme winds.

A design procedure should be developed using a load andresistance factor format. This will involve an analytical studymodeling structural response taking into account stabilityproblems, large deflection theory, occupancy and fire loading,influence of other fire protection features, and compartmentgeometry and ventilation. Design limit states and loadcombinations will need to be definied. The Fire Analysis ofSteel Building Systems (FASBUS II) computer program should beused as a basis for this work.

A five man-year level of effort is required.

RECOMMENDATION F2: DESIGN AIDS

DESIGN AIDS SHOULD BE DEVELOPED FOR CALCULATINGFIRE PROTECTION MATERIAL THICKNESSES FOR STEELBUILDING ELEMENTS.

Hundreds of ASTM El19 fire tests for establishing fireresistance ratings for steel columns, beams, floors, roofs and

47

walls have been conducted. Such tests are expensive and timeconsuming, and each test has a limited application by virtue ofthe construction details of that particular tested construction.Test data are available which can provide a basis for developinganalytical methods to predict fire resistance ratings for thesebuilding elements. This will provide an economical method fordetermining fire resistance ratings for untested steelconstructions which differ in construction details from thosetested. In addition, the ASTM El19 test of floors and roofsidentifies two fire resistance ratings - restrained andunrestrained. In order to prove that most steel floor designs ina building are restrained, AISI developed the FASBUS II computerprogram. Many code authorities require an analysis of the floorsystem using FASBUS II to prove the floor system is restrained.Design aids can reduce the need for an analysis of every floorconstruction.

Analyses should be conducted to determine the structuralresponse of typical steel floor systems under fire exposureconditions. FASBUS II can be used for this. Full-scale firetests may be required to provide additional data or verificationof equations for an engineering guide. This information shouldbe used to develop a simple guide for the structural engineer andbuilding official to agree on the use of restrained test resultsto establish fire protection material thicknesses on steel floorsand steel framing.


RECOMMENDATION F3: SHOP APPLIED FIRE PROTECTION

NEW FIRE PROTECTION MATERIALS SUITABLE FOR SHOPAPPLICATION TO STEEL MEMBERS SHOULD BE DEVELOPED.

Field application of fire protective coatings for steelstructures is costly. Material and application cost can amountto as much as 15 % of the cost of the steel frame. Existingmaterials cannot withstand the rigors of transportation anderection and are not suitable for shop application. Ablativecoatings which could be applied in the shop are prohibitivelyexpensive.

Background information should be collected to stimulatematerials manufacturers to develop new coatings. Thisinformation would include a definition of the size of thepotential market for such materials and the characteristicsrequired to insure adequate performance during shop application,transportation, erection and subsequent fire conditions.


48

RECOMMENDATION F4: LARGE AREA/LARGE VOLUMESTRUCTURES

MATHEMATICAL MODELS SHOULD BE DEVELOPED FORMODELING FIRE GROWTH IN LARGE AREA OR LARGEVOLUME STRUCTURES.

During the past two decades, a considerable amount ofresearch has been done on the modeling of fUlly developedcompartment fires. Much of this work is empirical and is basedon experiments involving relatively small compartments. Thereare many large area/large volume structures which arecommercially important to the steel industry. Examples includeatriums, covered shopping malls, transportation terminals,covered stadiums and sports complex's and indusrial plants. Itis questionable whether currently available models are applicableto such structures.

Fire models should be developed for large area/large volumestructures taking into account the following factors:ventilation, plume theory, relatively low fire loading, heatdissipation, and the probability of occurrence of fUlly developedfire conditions (flash over).


RECOMMENDATION FS: FIRE RESEARCH REVIEW

A COMPILATION AND ASSESSMENT OF FIRE RESEARCHAROUND THE WORLD SHOULD BE PREPARED ON APERIODIC BASIS.

There is a great deal of fire research being conductedthroughout the world. It is important that this work besummarized to minimize duplication of effort and enhance theopportunity for synergism. The summary should deal with allaspects of fire research of importance to building design. Itshould be updated on a periodic basis, perhaps every 3-5 years.


G. DESIGN LOADS

Loading characteristics such as load magnitude, duration andprobability of occurence are important elements of designcriteria for producing safe, economic structures. Research isneeded to characterize snow loads, wind loads and crane loads.Information is also needed on the response of structures andstructural elements to these loads.

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RECOMMENDATION Gl: CRANE LOADS

DESIGN LOADS SHOULD BE DETERMINED FOR OVERHEADAND UNDERHUNG CRANE SYSTEIIS.

There is a lack of information available on the lateralforces developed by crane systems in industrial buildings.

Research involving field investigations should be conductedto determine the magnitude of these loads. Information should beobtained on the probability of occurence of various loadcomb ina t ion s • Us in 9 t his in for mat ion, a n a 1 y tic a 1 andexperimental studies shoUld be carried out to establish fatiguerequirements, serviceability and strength design criteria.Design requirements should also be established.


RECOMMENDATION G2: DRIFTED SNOW

DESIGN LOAD DATA SHOULD BE DEVELOPED FORDRIFTED SNOW ON MULTI-LEVEL ROOFS.

Dr ift snow loads account for about 75 percent of snowrelated roof collapses. The problem is particularly importantfor low rise steel buildings with a change in roof elevation suchas industrial or manufacturing buildings with attached offices,school buildings, etc.

Needed research includes snow load measurements from fullscale structures and statistical analysis of drift snow load casehistories to determine the effects of geometrical andenvironmental parameters and establish annual probabilities ofexceedance.

A one man-year level of effort is required for a two tothree year period.

RECOMMENDATION G3: CLADDING BEHAVIOR

RATIORAL DESIGN PROCEDURES FOR CLADDING SHOULDBE DEVELOPED TAKING INTO ACCOUNT THE

. CHARACTERISTICS OF FLUCTUATING WIND PRESSURES,CLADDING MATERIALS AND CONSTRUCTION PRACTICES.

Pressure coefficients contained in current loading standardsand building codes reflect improvements in wind tunnel modelingof buildings. The techniques and instrumentation used to measuresurface pressures on wind tunnel models have not been

50

standardized. However, data obtained in full-scale and modelscale tests suggest that peak pressure coefficients based onlocalized fluctuations may be underestimated in the wind tunnelby 15 to 25 percent. Certain phenomena associated with flowseparation are not observed on wind tunnel pressure models·because of instrumentation limitations.

Research should be conducted to val idate wind tunnelmodeling techniques (including the associated instrumentation)through carefully conducted measurement programs in both modeland full-scale. The behavior of cladding elements subjected tofluctuating loads needs to be investigated systematically.Special laboratory equipment capable of duplicating actual loadtime histories obtained from field measurements will be needed.This information should be synthesized and rational designprocedures should be developed that account for fluctuatingpressures, cladding geometry and type of material, and fastenerdetails.

A three man-year level of effort is required for the fullscale measurements and a five man-year level of effort for thebehavior of cladding materials and development of designprocedures.

RECOMMENDATION G4: WIND LOADS ON LOW RISE BUILDINGS

THE VARIABILITY OF WIND LOADING ON LOW RISEBUILDINGS SHOULD BE BETTER DEFINED.

Additional information is needed on the effects of geometricand environmental factors on the variability of wind loads forlow rise buildings.

The required research includes a synthesis of informationavailable in the literature and wind tunnel studies.


RECOMMENDATION G5: INTERNAL PRESSURE LOADING

MODELS FOR MEAN AND PEAK INTERNAL PRESSURESASSOCIATED WITH WIND LOADS ON BUILDINGS SHOULDBE VERIFIED.

Internal pressures affect the design of cladding on low risebuildings and curtain wall systems in high rise buildings.Current analytical models for the mean and peak internalpressures are based on assumptions of the leakage distribution ofthe building envelope, the presence of large openings in theexterior, the distribution of interior leakage paths (doors,walls, etc.) and the building flexibility.

51

Experiments at both model scale and full-scale should beconducted to evaluate these models and develop improved designcriteria.


RECOIUIElmATION G6: BUILDING RESPONSE TO WIlmS

MEASUREMENTS SHOULD BE MADE OF THE RESPONSE OFFULL-SCALE STRUCTURES SUBJECTED TO WIlm LOADS.

Serviceability requirements and building performance asperceived by the occupants for high rise buildings subject towind loads are important design considerations. Additionalinformation on the dynamic performance of full-scale structuresis needed to develop improved design criteria.

Research should be conducted on full-scale high risestructures subjected to wind loads to obtain information on thefollowing: effective structural damping (nominal valuesavailable to the designer give concrete buildings an advantage),evaluation of building periods and comparison with calculatedvalues, building drift and rotation, and building accelerations.The work should be carried out in hurricane prone areas wherethere is a high probability of experiencing strong winds.


RECOMMENDATION G7: LARGE AREA ROOFS

MEASUREMENTS SHOULD BE MADE ON THE DISTRIBUTIONOF SNOW IN THE PRESENCE OF STRONG WINDS ONROOFS OF LARGE AREA.

Snow loads for roofs of low rise industrial, commercial orpUblic buildings where the roof system represents a major portionof the construction cost are an important design consideration.Current research in the United States and Canada includes fullscale monitoring programs, probabilistic modelin~ of theformation and statistical variability of snow loads and physicalmodel studies. The presence of strong winds, however, can causesignificant non-uniform deposition and drifting.

Snow load monitoring programs should be conducted on fullscale structures, with emphasis on roofs of large area or unusualshape, to obtain information on the joint occurrence of extremesnow and wihd loads, snow load distributions, and the duration ofdesign snow loads. The program should include re-examination ofexisting data to develop correlations with climatic information,development of improved physical modeling techniques for windtunnels and/or water flumes, and evaluation of existing

52

mathematical models.


53

ACKNOWLEDGMENTS

The success of the workshop was due to the enthusiasticparticipation of all the attendees.

The workshop Steering Committee played a key role indefining the research areas for the individual working groups andselecting the participants. The workshop was sponsored andjointly funded by the American Institute of Steel Construction,the American Iron and Steel Institute, the Metal BuildingManufacturers Association, the National Science Foundation andthe National Bureau of Standards. Funding for participation ofthe university researchers was provided by the National ScienceFoundation through the efforts of Dr. John Scalzi.

Several participants, who were unable to attend theworkshop, contributed problem statements for the working groupsto consider. We appreciate the contributions received fromTheodore Galambos, Hal Iyengar, Arthur Arndt, and Harry Weese.

John Gross ass isted in prepar ing the report and BruceEllingwood reviewed the final draft.

Mrs. Wanda Eader from the National Bureau of Standardsprov ided administrative support in planning and conducting theworkshop and typing the proceedings.

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APPENDIX A

WORKSHOP KEYNOTE SESSION

Remarks

by

Dr. Ernest AmblerDirector, National Bureau of Standards

I appreciate the opportunity to appear before you today towelcome you to the National Bureau of Standards. NBS is pleasedto sponsor this workshop along with the National ScienceFoundation, the American Institute of Steel Construction, theAmerican Iron and Steel Institute, and the Metal BuildingManufacturers Association.

This workshop has been convened to develop consensusrecommendations for steel building research, and to establishpriorities for consideration by industry and government. Inthese two days you will begin to establish the basis for acollaborative relationship among federal agencies, universityresearchers, design professionals, and the U.S. steel industry.

Here at the National Bureau of Standards we are very proudof our participation in many strong and productive cooperativeresearch efforts with industry, universities, and other federalagencies. We are all working together to assure the continuedgrowth and strengthening of our economy, especially through theapplication of science and technology to our industries. Ourresearch programs at NBS are enriched by the type of cooperationand collaboration in which you are expressing an interest by yourpresence here today.

I would like to give you some background on the rather longhistory of cooperation between NBS and the steel industry. Formore than 80 years, NBS has been working with the steel industryto improve the durability and performance of metals and alloys.Starting in 1903, NBS began work to determine the melting pointsof pure metals as part of our mission to perform basicmeasurements. In 1912, because of an alarming number of railroadaccidents, Congress appropriated special funds for NBS to conductmaterials investigations on railroad iron and steel. By 1913,our Metallurgy Division had been formed. In 1919, NBS providedthe first explanation of the phenomenon of age hardening ofmetals. By 1930, through improved technology, better steels werebeing used for rails and cars and the railroad accident rate fellby 2/3, from a high of 36,000 accidents in 1920.

World War II brought national concern for conservation ofstrategic raw materials such as chromium, tungsten, and

55

molybdenum used in steel manufacturing. NBS investigated "leanalloy" steels and developed new coatings and processes to helpmeet these concerns.

Since the post-war years, NBS has been actively pursuing ourpresent mission. We provide industry, government agencies, andscientific organizations with data, measurement methods, standardreference materials, concepts, and information on the fundamentalaspects of process ing, structure, phys ical properties, andperformance of metals and alloys.

Currently there are quite a few NBS programs supportive ofthe U.S. steel industry. For example: Steel producers use ourStandard Reference Materials (SRM's) to provide quality assurancefor their materials. These samples have specific chemical orphysical properties certified by the Bureau. They are used incalibrating instruments, checking chemical composition, andcontrolling production of various steels. Today, approximately30 percent of the 40,000 SRM's sold annually are to producers andusers of steel and metal alloys.

NBS is working with the American Iron and Steel Institute(AISI) to develop process control sensors for rapid measurementof temperature distributions and automatic detection of porosityduring manufacture. Also with AISI we are working to developdiagrams that will help designers select A36 structural steelproducts for load-bearing capacity and other performancecharacteristics related to fire safety.

The American Society for Metals (ASM) has raised $4 millionto cover its participation in a collaborative effort in which NBSis providing technical guidance on alloy phase diagrams. In 1982the National Association of Corrosion Engineers (NACE) and NBSestablished a cooperative corrosion data program to help reducecorrosion damage to the nation's infrastructure -- its bridges,buildings, industrial plants, vehicles, and utilities.

In our welding research program, NBS scientists are workingside-by-side with researchers sponsored by the welding ResearchCouncil (WRC) and the American Welding Institute (AWl), formerlyknown as the American Welding Technology Application Center(AWTAC). NBS welding research is developing the scientific basisto control the formation of flaws during welding, tonondestructively inspect welds to measure flaw size, and todevelop models to predict the effect of weld flaws on structuralintegrity. Most of those examples are collaborations involvingthe NBS Center for Materials Research.

In the Center for Building Technology (CBT) our research hassupported the development by the American Institute of SteelConstruction (AISC) of load and resistance factor design forsteel structures. CBT is currently working with AISC on aproject to determine the performance of connections in steelbraced frames. We have good reason to be proud of our supportfor the steel industry. We are delighted now to have the

56

opportunity to focus more attention on structural engineering.We are particularly excited about this new focus because of thecurrent interest in testing large scale structural components andsystems.

This afternoon you are scheduled to visit our l2-millionpound capacity Large Scale Structural Research Facility and the3-Dimensional Structural Testing Facility. The Large ScaleStructural Research Facility will be used later this year to testthe performance of full-scale bridge and building componentssUbjected to earthquake loads. NBS research facilities areavailable for cooperative work with industry and, under certainconditions, facilities are even available for proprietaryresearch.

In closing, I would like to state that we look forward tocontinued cooperation with the steel industry. I trust you willhave a productive workshop and that you will enjoy your meetinghere at NBS.

57

Remarks

by

Dr. John McTagueDeputy Director, Office of Science and

Technology policy

Thank you for the opportunity to get outside the Beltway fora brief period. It's nice to see real scientists and engineersagain. Even the air is different--there's no odor of fire andbrimstone coming from our neighbors in the Executive OfficeBuilding!

This workshop involving industry, government, and universityparticipants to discuss research needs for steel buildings comesat a highly symbolic time. Just over a month ago, thePresident's Commission on Industrial Competitiveness reported tothe President on ways to improve the u.s. position in anincreasingly international and increasingly competitive worldmarket. These eminent individuals--corporate CEO's, bankers,labor leaders, lawyers, and government officials--deliberated forsome eighteen months. They identified eight major factors whichaffect this, or any other, Nation's ability to compete.

They were items such as the cost of labor, the cost ofcapital, exchange rates, trade policies, etc. They then ratedthese as advantageous, neutral, or disadvantageous for the U.S.competitive position. The cost of labor is obviouslydisadvantageous for the U.S. competitive position, and wewouldn't have it any other way--we want American workers to be~he most prosperous in the world. None of the others Ienumerated possess potential advantage for us, either. The onlyadvantages we have lie in technology and talent. To quote fromthe report:

D ••••America owes much of its standard of living to U.S.preeminence in technology. In order to make technology acontinuing competitive advantage for the United states, weneed to do three basic things: (1) create a solidfoundation of science and technology that is relevantto commercial uses; (2) apply advances in knowledge tocommercial products and processes; and (3) protectintellectual property ••• "

So here you are today, one step ahead of the President'sCommission. You are already using the combined strengths of thethree sectors to cooperate to the advantage of all. If you aresuccessful in handling cooperative government-industry-universityresearch to advance the art in your field, and if your effortsare repeated in other fields, we as a Nation can be confident ofsuccess in this global competion.

58

It is also particularly fitting that you should convene atthe National Bureau of Standards, which has such a long andsuccessful track record in cooperative ventures to strengthen ourtechnology base. As the slogan of a former employer of minegoes, this is "Where Science Gets Down to Business."

Best wishes for a stimulating and successful workshop.

59

Remarks

by

John B. BuschChairman

American Institute of Steel Construction

Thank you for inviting me to be with you today. It is mypleasure to welcome you on behalf of a very important segment ofthe steel construction industry, the American Institute of SteelConstruction. MOst of you axe familiar with AISC, what it does,and where it has been. This morning I would like to use my timeto tell you about some of the things AISC is doing, where wecould be headed, and offer a few challenges.

First, a little background information. AISC is the tradegroup that represents the fabricated structural steel industrywith over 430 active member firms in the united States. AISCmember firms are involved in the fabrication of diversestructures for a wide range of building and non-buildingconstruction applications. The most prominent of these arecustom des igned stee I framed bui ldings and steel br idges.Throughout its 63 year history, AISC has been highly engineeringoriented with a strong emphasis on steel research and steeldesign techniques. It has pUblished many technical publicationsincluding the "bible" of the industry - the AISC Manual of SteelConstruction - which contains the well known AISC Code ofStandard Practice and the AISC Specifications for the Design,Fabrication and Erection of Structural Steel for Buildings.These documents are the basis for most steel building contractsand designs in this country as well as other parts of the wor Id.

Currently the fabricated structural steel industry isshipping over 4.5 million tons annually worth overS billiondollars. This is down from nearly 7.0 million tons and 8 billiondollars four years ago. This industry has been in a free falland the slide has not ended for many. Building steel representsapproximately 65% of the total tonnage shipped for our standardindustrial classification No. 3441.

AISC operates on a budget of nearly $4.0 million annuallywith a staff of over 55 people including its highly pr ized 20regional engineers located in key cities throughout the unitedStates. In a word, AISC is a "technical" organization.

A few years ago, AISC Headquarters were moved from New Yorkto Chicago. A change, and as part of that change, AISC decidedto market its technical expertise. That marketing effort, basedon statistical data and backed by hard core engineering andresearch studies, is gradually reaping benefits. This, despitethe overall decline in the capital sector of the economy and itsnegative impact on the fabricated structural steel industry. Ourobjective is to gain a bigger share of a shrinking pie for the

60

fabricated structural steel industry.

To organize for this goal a long range strategic planningtask group was formed over a year ago. Detailed studies arebeing developed, and the current schedule calls for thisstrategic plan to be presented to the industry by December ofthis year. The plan will incorporate five key objectives:

Market Share Penetration

Technology

Membership Enlargement and Involvement

Government Relations

Public Image

As you may note, technology is a vital factor in thisplanning.

The American Association of Engineering Societies in arecent paper points out that the United States is faltering inthe area of research and development and concludes that theactivities which move new technology from research to definedcommercial potential are inadequate. This group goes on toreport the strong correlation between research and improvedproductivity in manufacturing. Economist Edward F. Denison ratesthe various contributions to productivity as follows:

Technology •••••••••••••••••••••••••••• 38%

Capital ••••••••••••••••••••••••••••••• 26%

Quality of Labor •••••••••••••••••••••• 14%

Economies of Scale •••••••••••••••••••• 12%

Resource Allocation ••••••••••••••••••• IO%

Again, technology is the largest single factor to securestrength for our industry in the market place throughproductivity improvements. Some of the technological areas thathave been identified for progress include:

Computer - Aided Engineering

Flexible Manufacturing Systems

Office Operations

Advanced Manufacturing Methods

Advanced Software Systems

61

computers

Materials Technology

Energy

The American Association of Engineering Societies asks thekey question: Who is going to do these studies? They point outthat these long term programs require patience, organized andsteady administration along with continuous funding. Theyfurther suggest that new imaginative cooperative arrangementsderiving support from many sources, deserve urgent consideration.In Japan and Germany, institutes from many industries not onlywork closely with the academic experts but have substantialgovernment support as well. We need to look closer at thesepossibilities in the United States.

As a mature industry, we cannot compete dollar for dollarwith the high growth sectors of the economy in our researchefforts. But we can compete with them concept~ally in ourresearch direction. Let's look at a leading technical companyfor comparative purposes. United Technologies is a 16 billiondollar company with an after tax return on equity of over 16percent. Its growth rate for the past five years averages about8 percent per year (despite a major downturn in 1982). UnitedTechnologies employs over 200,000 people and includes thefOllowing companies in its conglomerate portfolio:

Carrier Air Conditioning

Otis Elevator

Essex

Building Systems Company

Pratt & Whitney

Elliott

Sikorsky

Norden, Inmont

Mostek and others

In their 1984 annual report, United Technologies states,

"High technology is the common denominator of allwe do. Through the successful management of technologywe are able to grow and to contribute to the worldeconomy. Few corporations spend as much as we do onresearch and development. Our long standing policy isto invest wisely substantial amounts of company funds in

62

advanced technology to yield superior products at thelowest possible cost."

Conceptually, despite the flair for high technology, theirgoals of superior products at the lowest possible cost should notbe that much different from ours. This appears to match myearlier remarks about having an improved position in the marketthrough innovative technology.

So, as you meet here today and tomorrow, the challenge isnot only to involve your detailed and specific thoughts, but alsoto encourage creative new thinking. Traditionally, the researchdone in our industry has been more market reacti ve than that ofanticipating the markets needs. AISC needs to provide you withmore help in this area so that our research dollars can be spentin the direction that meets the needs of the market to secure thebest results. I encourage you to consider these facts duringyour deliberations. From a fabricator's viewpoint, there aremany factors that affect cost, but five major variables need tobe collectively optimized to find the lowest cost. They are:

Engineering Labor

Drafting Labor

Shop Labor

Erection Labor

Raw Material Cost

Many steel designers correlate total cost savings with thereduced weight of the structure as it relates to raw materialcost only and totally neglect the other variables. How manyresearchers are guilty of the same process? In other words, weneed to be practical and consider all the factors that willaffect our products and services in the reality of the marketplace. I feel confident that this workshop can be an importantstep in that direction. Thank you.

63

Remarks

by

Robert B. PeabodyPresident, American Iron and Steel Institute

On behalf of the American Iron and Steel Institute, I wantto extend to all of you a warm welcome to this workshop on SteelResearch Needs for Buildings. We at AISI are genuinely pleasedto be one of the sponsors and to join with the American Instituteof Steel Construction, the Metal Building ManufacturersAssociation, the National Science Foundation, and the NationalBureau of Standards in an effort to identify realistic programsthat will advance the state-of-the-art and improve safety andeconomy in building design, fabrication and construction.

Building construction is a large market for steel. Weestimate some 4 mill ion tons of steel are consumed each year inbuildings of all types. You can understand, then, the importancewe place on this workshop.

This morning I would like to spend a few minutes to tell yousomething about AISI - who we are, what we do. Then I would liketo comment on AlSI structural research over the years and theimpact of this research on building construction. Finally, Ihope to leave you with some thoughts that you may wish toconsider during your deliberations over the next two days.

Who are we? AISI is an association of steel producingcompanies. It is truly "American" in that its membershipincludes companies from North, Central and South America whoaccount for 90% of the raw steel production in the WesternHemisphere.

Our activities embrace research and technology to improvethe steel manufacturing process, the collection and disseminationof statistics, public affairs, international trade and industrialrelations including health, safety and hygiene. In addition, theInstitute maintains field offices in cities throughout the UnitedStates, staffed by engineers who are responsible for industryactivities related to building codes and regulatory standardsthat effect the use of steel mill products in construction.

A key part of our code work has been the Institute'scontinuing studies of fire hazards and fire protection. Theobject here is greater fire safety at lower building costs. Infact, I see that one of your workshop sessions is dedicated tothe subject of needed fire research for buildings. We considerthis to be an area where real economies can be effected.

The Institute also engages in promotional activities ofgeneral interest to the steel industry. These include pUblicity,

64

booklets, trade show participation, motion pictures, seminars andeducational programs. In addition, special promotion programsare carried out by individual product promotion committees whosecompany members produce a particular steel mill product - hotrolled and cold finished bars, sheet and strip, large diameterline pipe, steel plate, structural steel and wire rope, to name afew.

With this brief description, you can see that AISI is amultifaceted organization engaged in all aspects that effect thesteel industry.

This, then, briefly, is who we are.

Now let's be specific and turn our attention to AISI'sstructural research. This, after all, is why we are here.AISI's research in the structural area began in earnest about 20years ago and it has embraced a number of topics incl uded in thisworkshop - connections and members, frames, seismic design, andload and resistance factor design. Throughout this period, themain objective has been to increase the economy and safety ofsteel construction by (1) developing new structural concepts, (2)improving and updating the provisions of various designspecifications and (3) preparing design guidelines andrecommendations for use by the engineer.

The eccentrically braced frame is an example o£ a newstructural concept developed through AISI research. The load andresistance factor design specification, another AISlproject,will give engineers a rational guide for building design.

I should note here our cooperative research programs withgovernment agencies, notably the Federal Highway Administrationand the National Science Foundation. We have a joint program nowunderway with the Federal Highway Administration to test a onehalf scale model of a prototype bridge designed using innovativestructural concepts. The model is to be tested sometime thisyear at the FHWA Turner-Fairbank Research Center, McLean,Virginia. Also, over the years, we have collaborated in projectsof the National Science Foundation relating to the design ofearthquake-resistant structures.

These joint efforts with the government have been animportant part of our research program.

In closing, I would like to leave you with a few thoughts.In the past, the steel producing and fabricating industries havebeen a major source of funding for structural related research.At one time these industries were able to freely support mostproposals that were submitted for consideration by variousresearch agencies. But, as you know, recent severe economicpressures have eroded the funds that were once available.Obviously, we must now evaluate and prioritize projects on a moreprecise basis. Economy and safety now become essential factorswhen considering a research topic for funding. In fact, the

65

words "economy" and "safety" are used in the stated objective ofthis workshop. I would urge you to keep these words in mindduring your discussions within each working session. Pleaseremember that the research priorities you set during the next twodays will become important guidelines upon which the steelindustry will base its future building research program.

The industry sincerely thanks you for the valuable time youare spending in its behalf and wishes you success in the arduoustask to which you have committed yourself. I know the results ofyour work will provide benefits for all. Thank you.

66

APPENDIX B

STEEL RESEARCH NEEDS FOR BUILDINGS

Program

TUESDAY« MARCH 5« 1985

9:009:45

9:45 10:00

10:00 10:30

Opening Remarks

- Ernest AmblerDirector, National Bureau of Standards

- John McTagueDeputy Director, Office of Science and

Technology Policy

- John BuschChairman, American Institute of Steel

Construction

- Robert PeabodyPresident, American Iron and Steel Institute

Workshop Introduction

Geerhard HaaijerAmerican Institute of Steel Construction

Charles CulverNational Bureau of Standards

Coffee Break

67

10:30 1:00

1:00 1:45

1:45 4:00

4:00 5:00

5:00 5:30

6:30 -

Working Group Sessions

Group 1 - Total Building SystemsChairman, Joseph Colaco

Group 2 - Connections and MembersChairman, Robert Disque

Group 3 - FramesChairman, William McGuire

Group 4 - Seismic DesignChairman, Mike Agbabian

Group 5 - Load and Resistance Factor DesignChairman, Ivan Viest

Group 6 - Fire ProtectionChairman, Richard Gewain

Group 7 - LoadsChairman, Dale Perry

Lunch

Working Group Sessions(continued)

Plenary SessionLecture Room A

Structures Laboratory Tour

Social Hour and Dinner

Speaker

Dr. Nam SuhAssistant Director of EngineeringNational Science Foundation-Cooperative Government/Industry/University Research-

68

WEDNESDAY r MARCH 6

9:00 1:00

1:00 1:45

1:45 4:00

4:00

4:15 -

Working Group Sessions(continued)

Lunch

Plenary SessionLecture Room A

Develop final recommendations

Closing Remarks

Adjourn

69

LOCATION:

National Bureau of StandardsGaithersburg, Maryland

SPONSORED BY:

National Bureau of StandardsNational Science FoundationAmerican Institute of Steel ConstructionAmerican Iron and Steel InstituteMetal Building Manufacturers Association

OBJECTIVE:

To develop consensus recommendations for steel buildingresearch and establish priorities for industry andgovernment consideration.

PARTICIPANTS:

Invited representatives from the steel industry, designprofessionals, Federal agency representatives anduniversity researchers.

STEERING COMMITTEE:

Charles G. Culver, NBS (Chairman)Joseph P. Colaco, CBM EngineersRobert O. Disque, AISCRichard Gewain, AISIGeerhard Haaijer, AISCNestor R. Iwankiw, AISCAlbert C. Kuentz, AISIWilliam McGuire, Cornell UniversityDale C. Perry, MBMAWerner H. Quasebarth, Atlas Machine and Iron WorksIvan M. Viest, Consulting Engineer

70

APPENDIX C

WORKSHOP PARTICIPAN'l'S

DESIGN PROFESSIONALS

Mr. Horatio AllisonPresidentAllison, McCormac & Nickolaus, P.A.11810 Parklawn DriveRockville, Maryland 20852

Mr. Irwin G. CantorOffice of Irwin G. Cantor919 Third AvenueNew York, New York 10022

Dr. Joseph P. ColacoPresidentCBM Engineers, Inc.1700 West Loop South - Suite 830Houston, Texas 77027-3092

Mr. Henry J. DegenkolbH. J. Degenkolb Associates, Engineers350 Sansome Street, Room 500San Francisco, California 94104

Dr. James M. FisherVice PresidentComputerized Structural Design, Inc.5678 W. Brown Deer RoadMilwaukee, Wisconsin 53223

Mr. Jerome S.B. IfflandPresident, Iffland Kavanagh Waterbury1501 BroadwayNew York, New York 10036

Mr. Socrates IoannidesSenior EngineerStanley D. Lindsey & Associates, Ltd.1906 West End AvenueNashville, Tennessee 37203-2371

Dr. Stanley D. LindseyPresidentStanley D. Lindsey & Associates, Ltd.1906 West End AvenueNashville, Tennessee 37203-2371

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Dr. Walter p. Moore, Jr.Chairman & PresidentWalter P. Moore & Associates, Inc.2905 Sackett StreetHouston, Texas 77098

Mr. Clarkson W. PinkhamPresidentS.B. Barnes & Associates2236 Beverly Blvd.Los Angeles, California 90057

Mr. Dell ShieldsVice PresidentHerrick CorporationP.O. Box 3007Hayward, California 94540

Mr. Leslie V. ShuteVice PresidentTurner Construction Company633 3rd AvenueNew York, New York 10017

Dr. John D. StevensonPresident, Stevenson & Associates9217 Midwest AvenueCleveland, Ohio 44125

Mr. Edward J. TealSeismic Engineering Associates, Ltd.1300 4th StreetSanta Monica, California 90401

Mr. Raymond H.R. TideWiss, Janney, Elstner, Associates, Inc.330 Pfingsten RoadNorthbrook, Illinois 60062

Dr. Ivan M. ViestConsulting EngineerP.O. Box 1428Bethlehem, Pennsylvania 18016

Mr. Kenneth B. Wiesner, P.E.LeMessurier Associates/SCI1033 Massachusetts AvenueCambridge, Massachusetts 02238

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INDQSTRY BBPRESBI'J.'ATlVES

Mr. Edward P. Becker, P.E.Chief EngineerLehigh structural Steel CompanyBox 626One Allen StreetAllentown, Pennsylvania 18015

Mr. Delbert F. BoringRegional Director, Construction

Codes & StandardsAmerican Iron and Steel Institute4937 West Broad StreetColumbus, Ohio 43228

Mr. Roger L. BrockenbroughResearch ConsultantHeavy Products DivisionU.S. Steel CorporationTechnical CenterOne Tech Center DriveMonroeville, Pennsylvania 15146

Mr. John H. BuschPresident, Haven-Busch Company3443 Chicago Drive, s.w.Grandville, Michigan 49418

Mr. Andrew K. CourtneyChief EngineerOwen Steel Company, Inc.801 Blossom StreetP.O. Box 1698Columbia, South Carolina 29202

Mr. Robert O. DisqueAssistant Director of EngineeringAmerican Institute of Steel Construction, Inc.The Wrigley Bldg.400 North Michigan AvenueChicago, Illinois 60611-4185

Mr. William Y. EplingDirector of Government AffairsAmerican Institute of Steel Construction, Inc.Suite 4001629 K Street, NW

.Washington, DC 20006

73

Mr. Walter H. FleischerSenior structural ConsultantBethlehem Steel Corporation255 SGOBethlehem, Pennsylvania 18016

Mr. Richard GewainChief, Fire Protection EngineerAmerican Iron & Steel Institute1000 16th Street, NWwashington, DC 20036

Mr. Michael GilmorManager of EngineeringCanadian Institute of Steel Construction201 Consumers RoadSuite 300Willowdale, Ontario, M2J 4G8Canada

Mr. John D. GriffithsVice President - EngineeringPaxton & Vierling Steel Co.P.O. Box 1085Omaha, Nebraska 68101

Mr. Joshua GurmanAmerican Iron and Steel Institute1000 16th Street, NWwashington, DC 20036

Dr. Geerhard HaaijerVice PresidentAmerican Institute of Steel ConstructionThe Wrigley Bldg.400 North Michigan AvenueChicago, Illinois 60611-4185

Mr. J. W. HotchkiesManager, Market Development EngineeringThe Algoma Steel Corporation, Ltd.Mississauga Executive Center, Suite 900Four Robert Speck ParkwayMississauga, OntarioCanada L4Z lSI

74

Mr. Nestor IwankiwAssistant Director of EngineeringAmerican Institute of Steel ConstructionThe wrigley Bldg.400 North Michigan AvenueChicago, Illinois 60611-4185

Mr. Juris Jauntirans3210 Watlong streetInland Steel CompanyEast Chicago, Indiana 46312

Mr. David C. JeanesAmerican Iron and Steel Institute1000 16th Street, NWWashington, DC 20036

Mr. Donald L. JohnsonSenior Research EngineerButler Manufacturing CompannyResearch Center135th Street and Botts RoadGrandview, Missouri 64030

Mr. Larry KloiberVice PresidentL. L. LeJeune Company118 West 60th StreetMinneapolis, Minnesota 55419

Mr. Henry V. KominekRegional DirectorConstruction Codes & StandardsAmerican Iron & Steel Institute1150 Wilmette AvenueWilmette, Illinois 60091

Mr. Albert C. KuentzStaff RepresentativeAmerican Iron & Steel Institute1000 16th Street, NWWashington, DC 20036

75

Mr. Hank MartinRegional Director, Codes &

StandardsAmerican Iron & Steel Institute671 Newcastle Road, Suite 1Newcastle, California 95658-9702

Mr. Daniel M. McGee, P.E.Regional Director, Construction Codes

& Standards .American Iron & Steel InstituteP.O. Box 311Matawan, New Jersey 07747

Mr. William E. MooreVice President - EngineeringTaurrier Street and BredfordP.O. Box 753Ferro Products CompanyCharleston, West Virginia 25323

Mr. Heinz PakEngineering ConsultantUnited States Steel Corporation600 Grant StreetPittsburgh, Pennsylvania 15230

Mr. Robert B. PeabodyPresident, American Iron &

Steel Institute1000 16th Street, NWWashington, DC 20036

Dr. Dale C. PerryMetal BUilding Manufacturers AssociationDirector of Engineering and Research1230 Keith BuildingCleveland, Ohio 44115

Mr. Werner H. QuasebarthPresidentAtlas Machine & Iron Works, Inc.7308 Wellington RoadGainesville, Virginia 20065

76

Mr. Bill RicheyVice President EngineeringHavens Steel Company7219 East 17th StreetKansas City, Missouri 64126-2890

Mr. Robert E. RollManager of Structural Shapes & Piling MarketingBethlehem Steel CorporationBethlehem, Pennsylvania 18016

Mr. Dell ShieldsVice PresidentHerrick CorporationP.O. Box 3007Hayward, California 94540

Mr. Gary F. TilsonRegional Director, Codes & StandardsAmerican Iron & Steel Institute798 Rays Road, Suite 105AStone Mountain, Georgia 30083

Dr. William ThorntonChief EngineerCives Steel Company411 Rouse LaneP.O. Box 768180Atlanta, Georgia 30338

Ms. Lisa VornholtRegional DirectorAmerican Iron and Steel Institute13500 Midway Road, Suite 111Dallas, Texas 75234

Mr. Walter G. WellsAmerican Iron and Steel Institute1000 16th Street, NWWashington, DC 20036

Mr. R. T. WillsonAmerican Iron and Steel Institute1000 16th Street, NWWashington, DC 20036

Mr. James WootenChief, Structural Design EngineerAFCO Steelp.O. Box 2311423 East Sixth StreetLittle Rock, Arkansas 72201

77

UNIVERSITY RESEARCHERS

Dr. Joel I. AbramsChairman, Department of Civil EngineeringUniversity of Pittsburgh949 Benedum HallPittsburgh, Pennsylvania 15261

Professor Mihran S. AgbabianChairman, Department of Civil EngineeringUniversity of Southern CaliforniaLos Angeles, California 90089

Dr. Wai Fah ChenProfessor & Head, Structural EngineeringSchool of Civil EngineeringCivil Engineering BuildingPurdue UniversityWest Lafayette, Indiana 47907

Professor John W. FisherFritz Engineering LaboratoryBuilding 13Lehigh UniversityBethlehem, Pennsylvania 18015

Professor Kurt H. GerstleDepartment of Civil Environmental and

Architectural EngineeringUniversity of ColoradoCampus Box 428Boulder, Colorado 80309

Dr. Robert D. HansonProfessor of Civil EngineeringUniversity of MichiganDepartment of Civil Engineering304 West Engineering Bldg.Ann Arbor, Michigan 48109-1092

Professor Helmut KrawinklerDepartment of Civil EngineeringStanford UniversityStanford, California 94305

78

Professor Le-Wu LuCivil Engineering DepartmentFritz Engineering LaboratoryLehigh UniversityBethlehem, Pennsylvania 18015

Professor William McGuireCornell UniversitySchool of Civil and Environmental EngineeringHollister HallIthaca, New York 14853

Professor Thomas M. MurrayUniversity of OklahomaSchool of Civil Engineering202 W. Boyd Street, Room 334Norman, Oklahoma 73019

Dr. Michael J. O'RourkeAssociate Professor, Civil EngineeringRensselaer Polytechnic InstituteTroy, New York 12181

Professor Egor PopovProfessor Emeritus of Civil EngineeringUniversity of California, BerkeleyCollege of EngineeringBerkeley, California 94720

Dr. James B. RadziminskiUniversity of South CarolinaDepartment of Civil EngineeringCollege of EngineeringColumbia, South Carolina 29208

Dr. Charles W. RoederDepartment of Civil EngineeringUniversity of Washington233 More Hall, FX-IOSeattle, Washington 98195

79

Dr. D. SurryBoundary Layer Wind Tunnel LaboratoryFaculty of Engineering ScienceLondon, OntarioCanada N6A 5B9

Professor Joseph A. YuraWarren Bellows Professor of Civil EngineeringUniversity of Texas at AustinDepartment of Civil Engineering10100 Burnet RoadAustin, Texas 78758-4497

80

GOVERRMENT REPRESENTATIVES

Mr. Gifford AlbrightNational Science Foundation1800 G Street, NWwashington, DC 20550

Dr. Hans AsharResearch ManagerU.S. Nuclear Regulatory Commission(NL 5650)Washington, DC 20555

Dr. Charles G. CulverChief, Structures DivisionNational Bureau of StandardsGaithersburg, Maryland 20899

Dr. Robert M. DinnatAssociate Technical DirectorConstruction Engineering Research LaboratoryU.S. Army Corps of EngineersBox 4005Champaign, Illinois 61820

Dr. Bruce R. EllingwoodLeader, Structural EngineeringStructures DivisionNational Bureau of StandardsGaithersburg, Maryland 20899

Mr. Michael GausNational Science Foundation1800 G Street, NWwashington, DC 20550

Dr. John L. GrossResearch EngineerStructures DivisionNational Bureau of StandardsGaithersburg, Maryland 20899

Dr. H. S. LewLeader, Construction SafetyStructures DivisionNational Bureau of StandardsGaithersburg, Maryland 20899

Dr. Edgar V. LeyendeckerLeader, Earthquake Hazards ReductionStructures DivisionNational Bureau of StandardsGaithersburg, Maryland 20899

81

Dr. Richard D. MarshallStructures DivisionNational Bureau of StandardsGaithersburg, Maryland 20899

Dr. John McTagueDeputy DirectorOffice of Science & Technology PolicyExecutive Office of the PresidentRoom 5005New Executive Office BuildingWashington, DC 20506

Mr. Irving E. Minkin, P.E.Deputy CommissionerNYC Department of Buildings120 Wall StreetNew York, New York 10005

Dr. Jack ScalziNational Science Foundation1800 G Street, NWWashington, DC 20550

Dr. Emil SimiuStructural Research EngineerStructures DivisionNational Bureau of StandardsGaithersburg, Maryland 20899

Dr. Nam SuhAssistant Director of EngineeringNational Science Foundation1800 G Street, NWWashington, DC 20005

Mr. Michael YachnisChief EngineerNaval Facilities Engineering Command(04B)Department of the Navy200 Stovall StreetAlexandria, Virginia 22332-2300

*u.s. GOVERNMENT PRINTING OFFICE, 1985-461-105'20139

82

NBSTechnical Publications

Periodical

Journal of Research-The Journal of Research of the National Bureau of Standards reports NBS researchand development in those disciplines of the physical and engin~ring sciences in which the Bureau is active.These include physics, chemistry, engineering, mathematics, and computer sciences. Papers cover a broadrange of subjects, with major emphasis on measurement methodology and the basic technology underlyingstandardization. Also included from time to time are survey articles on topics closely related to the Bureau'stechnical and scientific programs. Issued six times a year.

Nonperiodicals

Monograph~Majorcontributions to the technical literature on various subjects related to the Bureau's scienti fic and technical activities.Handbooks-Recommended codes of engineering and industrial practice (including safety codes) developed incooperation with interested industries, professional organizations, and regulatory bodies.Special Publications-Include proceedings of conferences sponsored by NBS, NBS annual repons, and otherspecial publicatiohs appropriate to this grouping such as wall charts, pocket cards, and bibliographies.Applied Mathematics Series-Mathematical tables, manuals, and studies of special interest to physicists,engineers, chemists, biologists, mathematicians, computer programmers, and others engaged in scientific andtechnical work. ..

National Standard Reference Data Series-Provides quantitative data on the physical and chemical propertiesof materials, compiled from the world's literature and critically evaluated. Developed under a worldwide program coordinated by NBS under the authority of the National Standard Data Act (public Law 90-396).NOTE: The Journal of Physical and Chemical Reference Data (JPCRD) is published quanerly for NBS bythe American Chemical Society (ACS) and the American Institute of Physics (AlP). Subscriptions, reprints,and supplements are available from ACS, 1155 Sixteenth St., NW, Washington, DC 20056.Building Science Series-Disseminates technical information developed at the Bureau on building materials,components, systems, and whole structures. The series presents research results, test methods, anq performance criteria related to the structural and environmental functions and the durability and safetycharacteristics of building elements and systems.Technical Notes-Studiesm repons which are complete in themselves but restrictive in their treatment of asubject. Analogous to monographs but not so comprehensive in scope or definitive in treatment of the subjectarea. Often serve as a vehicle for final repons of work performed at NBS under the sponsorship of othergovernment agencies. .Voluntary Product Standards-Developed under procedures published by the Department of Commerce inPart 10, Title 15, of the Code of Federal Regulations. The standards establish nationally recognized requirements for products, and provide all concerned interests with a basis for common understanding of thecharacteristics of the products. NBS administers this program as a supplement to the activities of the privatesector standardizing organizations.Consumer Information Series-Practical information, based on NBS research and experience, covering areasof interest to the consumer. Easily understandable language. and illustrations provide useful bad.-groundknowledge for shoppiIl.$ in today's technological marketplace.Order the above NBS publications from: Superintendent of Documents, Government Printing Qffice,Washington, OC 20402. .Order the following NBS publicatiollS-FlPS and NBSIR's-from the National Technical Information Ser-vice, Springfield, VA 22161. .

Federal Information Processing Standards Publications (BPS PUB}-Publications in this series collectivelyconstitute the Federal .Information Processing Standards Register. The Register serves as the official source ofinformation in the Federal Government regarding standards issued by NBS pursuant to the Federal Propertyand Administrative Services Act of 1949 as amended, Public Law 89-306 (79 Stat. 1127), and as implementedby Executive Order 11717 (38 FR 12315, dated May 11, 1973) and Part 6 of Title 15 CFR (Code of FederalRegulations). . .NBS Interagency ReportS (NBSIR}-A speciai series' of interim or fmal repons on work performed by NBSfor outside sponsors (both government and non-government). In general, initial distribution is handled by thesponsor; public distritJution is by the National Technical Information Service, Springfield, VA 22161, in papercopy or microfic.he form.