DESIGN OF STEEL STRUCTURES FOR BLAST-RELATED PROGRESSIVE COLLAPSE
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41 DESIGN OF STEEL STRUCTURES FOR BLAST-RELATED PROGRESSIVE COLLAPSE RESISTANCE RONALD HAMBURGER, S.E. & ANDREW WHITTAKER, S.E. Ronald Hamburger Andrew Whittaker BIOGRAPHIES Ron Hamburger: Ronald Hamburger is a structural engineer and principal with Simpson Gumpertz & Heger in San Francisco. Mr. Hamburger has nearly 30 years of experience in structural design, evaluation, upgrade, research, code and standards development, and education. Mr. Hamburger serves as chair of the BSSC Provisions Update Committee, AISC’s Connection Prequalification Review Panel, and is vice-chair of the AWS D1.1 Seismic Task Committee. Further, he is a member of the ASCE-7 committee, is President-Elect of the National Council of Structural Engineering Associations and is the Project Director for the ATC-58 project on performance-based earthquake engineering. Mr. Hamburger was a member of the joint FEMA/ASCE Building Performance Assessment Team that studied the collapse of New York’s World Trade Center on September 11, 2001. Andrew Whittaker: Andrew Whittaker is an Associate Professor of Civil Engineering at the University at Buffalo, with research and design-professional interests in earthquake and blast engineering. He is a licensed Structural Engineering in the State of California. Dr. Whittaker serves as a member of the ASCE committees that address loadings on structures, blast engineering, and earthquake protective systems, ACI Committee 349 on reinforced concrete nuclear structures, BSSC Technical Subcommittee 12 on seismic isolation and passive energy dissipation systems for new buildings, as Vice President of the Consortium of Universities for Research in Earthquake Engineering, and as the Structural Team Lead for the ATC-58 project on performance-based earthquake engineering. ABSTRACT Structural steel framing is an excellent system for providing building structures the ability to arrest collapse in the event of extreme damage to one or more vertical load carrying elements. The most commonly employed strategy to provide progressive collapse resistance is to employ moment-resisting framing at each floor level so as to re- distribute loads away from failed elements to alternative load paths. Design criteria commonly employed for this purpose typically rely on the flexural action of the framing to redistribute loads and account for limited member ductility and overstrength using elastic analyses to approximate true inelastic behavior. More efficient design solutions can be obtained by relying on the development of catenary behavior in the framing elements. However, in order to reliably provide this behavior, steel framing connections must be capable of resisting large tensile demands simultaneously applied with large inelastic flexural deformations. Moment connections prequalified for use in seismic service are presumed capable of providing acceptable performance, however, research is needed to identify confirm that these connection technologies are capable of reliable service under these conditions. In addition, some refinement of current simplified analysis methods is needed.
