UPCOMING CHANGES TO THE AISC SEISMIC PROVISIONS

摘要

The 1994 Northridge earthquake, resulted in an unprecedented level of interest in the seismic performance of steel frame structures. This interest led to major research and development programs including the FEMA/SAC Steel Program. As a result of these efforts, significant modifications to the U.S. seismic design provisions for steel structures have taken place. The AISC Seismic Provisions were almost completely re-written in 1997, with additional major modifications in 1999 and late in 2000. In addition to updating the requirements for existing systems to be consistent with recent research results and current thinking, these provisions also have incorporated a number of new systems that can be used for various applications. The contents of the 1997 Seismic Provisions and the two supplements will be briefly summarized in this paper. This paper will focus on the 2002 AISC Seismic Provisions that were recently completed and will be the basis for the steel seismic design provisions in the 2002 NFPA 5000 and the 2003 International Building Code. The 2002 Seismic Provisions incorporate information from the final FEMA/SAC recommendations presented in FEMA 350 through 355. Work on two new systems (steel plate shear wall and buckling restrained braced frames) that are also presently under development will also be discussed.