THE NEXT GENERATION OF CODES FOR SEISMIC ISOLATION IN THE UNITED STATES AND REGULATORY BARRIERS TO SEISMIC ISOLATION DEVELOPMENT

Design requirements for seismically isolated buildings were first codified in the United States as an appendix to the 1991 Uniform Building Code. In the intervening years, those provisions have not been significantly changed. Seismic isolation has been perceived as expensive, complicated, and time-consuming in both design and execution. While these criticisms were valid the fault does not lie with the technology itself. The drawbacks to using seismic isolation stemmed from the design professions ability to fully quantify the benefits of the technology coupled with the conservative and burdensome code requirements. The paper describes proposed revisions to Chapter 17 of ASCE 7-10 that have been developed by a committee of 10 over the past 18 months. If adopted they would be applicable to ASCE 716 provisions. The recommendations are the most significant modifications since the 1991 provisions were adopted. If adopted the recommended changes will make the design and implementation process as economic and as easy to implement as possible and should expand the use of seismic isolation technology in the US.