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Recent damaging earthquakes in the United States and abroad have demonstrated oc3dd "8}@
the earthquake vulnerability of highway bridges that were designed to existing seismic /H%<oAjp6
codes. To address this inadequate performance, extensive research programs have been qr'x0r|<>
carried out. These programs have advanced the state of the art to the point where a new 0V>ESyae5
specification for seismic design is necessary to take advantage of new insight into Rg8m4x w
ground motion and geotechnical effects, improved performance criteria, and more BDm88< ]
advanced analytical and design methodologies. @`IXu$ Wm(
The objective of this research was to enhance safety and economy through the [V2omSZo
development of new load and resistance factor design (LRFD) specifications and commentary '!+ P{
for the seismic design of bridges. The research considered design philosophy u8<&F`7j
and performance criteria, seismic loads and site effects, analysis and modeling, and 02 79g
design requirements. The specifications are nationally applicable with provisions for ;* wT,2;
all seismic zones and are intended to be integrated into the AASHTO LRFD Bridge 2Z/][?Jj{
Design Specifications. <*A|pns
The research was performed by a joint venture of the Applied Technology Council \ f /!
and the Multidisciplinary Center for Earthquake Engineering Research. The report /jjW/ lr
fully documents the methodology used to develop the recommended specifications. M|[@znzR<
The recommended specifications provided the technical basis for a stand-alone set of Ere?d~8
provisions prepared by the ATC/MCEER Joint Venture titled “Recommended LRFD #7-kL7 MK]
Guidelines for the Seismic Design of Highway Bridges.” AASHTO will consider these /jZaU`
provisions for adoption as a Guide Specification in 2002.
