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Recent damaging earthquakes in the United States and abroad have demonstrated s_D7?o
the earthquake vulnerability of highway bridges that were designed to existing seismic <KHB/7
codes. To address this inadequate performance, extensive research programs have been 6 u8`,& U
carried out. These programs have advanced the state of the art to the point where a new w $61+KH K
specification for seismic design is necessary to take advantage of new insight into 6kI q6rWF9
ground motion and geotechnical effects, improved performance criteria, and more "TN}=^A\F
advanced analytical and design methodologies. #'$CC<*vy
The objective of this research was to enhance safety and economy through the A{&Etu( K
development of new load and resistance factor design (LRFD) specifications and commentary .!)7x3| $[
for the seismic design of bridges. The research considered design philosophy w:z_EV!&
and performance criteria, seismic loads and site effects, analysis and modeling, and ~@itZ,d\
design requirements. The specifications are nationally applicable with provisions for a` /[\ K6
all seismic zones and are intended to be integrated into the AASHTO LRFD Bridge {nj\dU
Design Specifications. g\ <Lb
The research was performed by a joint venture of the Applied Technology Council -pg7>vO q
and the Multidisciplinary Center for Earthquake Engineering Research. The report DU}q4u@ )
fully documents the methodology used to develop the recommended specifications. 2eyvY|:Q>
The recommended specifications provided the technical basis for a stand-alone set of 9&rn3hmP
provisions prepared by the ATC/MCEER Joint Venture titled “Recommended LRFD %[ NefA(
Guidelines for the Seismic Design of Highway Bridges.” AASHTO will consider these tkNuM0
provisions for adoption as a Guide Specification in 2002.
