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Recent damaging earthquakes in the United States and abroad have demonstrated ,k=8|=aF
the earthquake vulnerability of highway bridges that were designed to existing seismic _/'VD!(MV
codes. To address this inadequate performance, extensive research programs have been <h ;_:
carried out. These programs have advanced the state of the art to the point where a new :U *8S\$
specification for seismic design is necessary to take advantage of new insight into z&B9Yu4M7
ground motion and geotechnical effects, improved performance criteria, and more ];"40 /X
advanced analytical and design methodologies. tv`b# #
The objective of this research was to enhance safety and economy through the QqRF?%7q"q
development of new load and resistance factor design (LRFD) specifications and commentary '2h y%
for the seismic design of bridges. The research considered design philosophy 5gII|8>rQ
and performance criteria, seismic loads and site effects, analysis and modeling, and >*opE I+
design requirements. The specifications are nationally applicable with provisions for q
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all seismic zones and are intended to be integrated into the AASHTO LRFD Bridge e&*b{>1*
Design Specifications. Kn<+Au_]L
The research was performed by a joint venture of the Applied Technology Council a
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and the Multidisciplinary Center for Earthquake Engineering Research. The report -FI)o`AE
fully documents the methodology used to develop the recommended specifications. Vo+.s#wN`h
The recommended specifications provided the technical basis for a stand-alone set of M@P% k`6C
provisions prepared by the ATC/MCEER Joint Venture titled “Recommended LRFD aSu^
Guidelines for the Seismic Design of Highway Bridges.” AASHTO will consider these ?{jey_]M
provisions for adoption as a Guide Specification in 2002.
