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Recent damaging earthquakes in the United States and abroad have demonstrated '"T9y=9]s
the earthquake vulnerability of highway bridges that were designed to existing seismic ;_#<a*f
codes. To address this inadequate performance, extensive research programs have been M9~6ry-_
carried out. These programs have advanced the state of the art to the point where a new $"ACg!=M
specification for seismic design is necessary to take advantage of new insight into ;tC$O~X
ground motion and geotechnical effects, improved performance criteria, and more Y|S>{$W
advanced analytical and design methodologies. V[0
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The objective of this research was to enhance safety and economy through the &qP0-x)
development of new load and resistance factor design (LRFD) specifications and commentary n(W&GSj|u9
for the seismic design of bridges. The research considered design philosophy [l}H% S
and performance criteria, seismic loads and site effects, analysis and modeling, and 7Q9| P?&:z
design requirements. The specifications are nationally applicable with provisions for 0 YAH[YF
all seismic zones and are intended to be integrated into the AASHTO LRFD Bridge dF><XZph
Design Specifications. > D%
The research was performed by a joint venture of the Applied Technology Council ! ~tf0aY
and the Multidisciplinary Center for Earthquake Engineering Research. The report Q5HSik4
fully documents the methodology used to develop the recommended specifications. }/QtIY#I
The recommended specifications provided the technical basis for a stand-alone set of Vwb_$Yi+]
provisions prepared by the ATC/MCEER Joint Venture titled “Recommended LRFD FuC \qF
Guidelines for the Seismic Design of Highway Bridges.” AASHTO will consider these TE6]4 E*
provisions for adoption as a Guide Specification in 2002.
