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Recent damaging earthquakes in the United States and abroad have demonstrated x{w|Hy
the earthquake vulnerability of highway bridges that were designed to existing seismic v
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codes. To address this inadequate performance, extensive research programs have been [W$Mn.5<s
carried out. These programs have advanced the state of the art to the point where a new *(r9c(x a
specification for seismic design is necessary to take advantage of new insight into [>p!*%m
ground motion and geotechnical effects, improved performance criteria, and more $0$sDN6)x
advanced analytical and design methodologies. O!dS;p-F
The objective of this research was to enhance safety and economy through the pd: YR;
development of new load and resistance factor design (LRFD) specifications and commentary AG vhSd7
for the seismic design of bridges. The research considered design philosophy Kz q^f=p
and performance criteria, seismic loads and site effects, analysis and modeling, and sxF2ku4A
design requirements. The specifications are nationally applicable with provisions for 9 $X" D
all seismic zones and are intended to be integrated into the AASHTO LRFD Bridge W!X Buk-
Design Specifications. mpwh=
The research was performed by a joint venture of the Applied Technology Council o?M ;f\Fy
and the Multidisciplinary Center for Earthquake Engineering Research. The report O zC%6;6h
fully documents the methodology used to develop the recommended specifications. *zweZG8:
The recommended specifications provided the technical basis for a stand-alone set of NkGtZ.!pk
provisions prepared by the ATC/MCEER Joint Venture titled “Recommended LRFD /K!f3o+
Guidelines for the Seismic Design of Highway Bridges.” AASHTO will consider these [Pp#r&4H
provisions for adoption as a Guide Specification in 2002.
