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Recent damaging earthquakes in the United States and abroad have demonstrated e euAo&L&
the earthquake vulnerability of highway bridges that were designed to existing seismic ] _#[o S
codes. To address this inadequate performance, extensive research programs have been N[=nh)m7b
carried out. These programs have advanced the state of the art to the point where a new XjL( V1
specification for seismic design is necessary to take advantage of new insight into -BN W\ ]}
ground motion and geotechnical effects, improved performance criteria, and more BXm{x6\
advanced analytical and design methodologies. ?jb7Oq#[
The objective of this research was to enhance safety and economy through the i"U3wt |A
development of new load and resistance factor design (LRFD) specifications and commentary JCE364$$"
for the seismic design of bridges. The research considered design philosophy wwE9|'Ok
and performance criteria, seismic loads and site effects, analysis and modeling, and <o
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design requirements. The specifications are nationally applicable with provisions for >YPfk=0f0
all seismic zones and are intended to be integrated into the AASHTO LRFD Bridge $8X?|fV)
Design Specifications. `/Z8mFs Y
The research was performed by a joint venture of the Applied Technology Council `\#Q r|GC
and the Multidisciplinary Center for Earthquake Engineering Research. The report 5E~][. d
fully documents the methodology used to develop the recommended specifications. 4}96|2L5
The recommended specifications provided the technical basis for a stand-alone set of :90 DS_4
provisions prepared by the ATC/MCEER Joint Venture titled “Recommended LRFD iSH Nt0Nl
Guidelines for the Seismic Design of Highway Bridges.” AASHTO will consider these DlTV1X-^1
provisions for adoption as a Guide Specification in 2002.
