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Recent damaging earthquakes in the United States and abroad have demonstrated m^Glc ?g<
the earthquake vulnerability of highway bridges that were designed to existing seismic 5Dd:r{{ Q
codes. To address this inadequate performance, extensive research programs have been 4Ac}(N5D@
carried out. These programs have advanced the state of the art to the point where a new "CB RPp
specification for seismic design is necessary to take advantage of new insight into > VP5vkv=
ground motion and geotechnical effects, improved performance criteria, and more ;,k=<]
advanced analytical and design methodologies. U9
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The objective of this research was to enhance safety and economy through the pl|h>4af
development of new load and resistance factor design (LRFD) specifications and commentary Fwb5u!_,
for the seismic design of bridges. The research considered design philosophy L!,d"wuD
and performance criteria, seismic loads and site effects, analysis and modeling, and aZ6'|S;
design requirements. The specifications are nationally applicable with provisions for 6| 5H=*)DH
all seismic zones and are intended to be integrated into the AASHTO LRFD Bridge "Kq>#I'%W
Design Specifications. ~q 7;8<U
The research was performed by a joint venture of the Applied Technology Council E~ qQai=]
and the Multidisciplinary Center for Earthquake Engineering Research. The report w//omF'`
fully documents the methodology used to develop the recommended specifications. 4^[
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The recommended specifications provided the technical basis for a stand-alone set of yPoSJzC=[
provisions prepared by the ATC/MCEER Joint Venture titled “Recommended LRFD ytiyF2Kp
Guidelines for the Seismic Design of Highway Bridges.” AASHTO will consider these g8RPHj vZ
provisions for adoption as a Guide Specification in 2002.
