nchrp472 MM+x}g.?
Recent damaging earthquakes in the United States and abroad have demonstrated n\X' 2
the earthquake vulnerability of highway bridges that were designed to existing seismic . 5cL+G1k#
codes. To address this inadequate performance, extensive research programs have been nTy8:k ']
carried out. These programs have advanced the state of the art to the point where a new )sONfn
specification for seismic design is necessary to take advantage of new insight into U%<E9G594
ground motion and geotechnical effects, improved performance criteria, and more @e`%'
advanced analytical and design methodologies. mgO D J
The objective of this research was to enhance safety and economy through the ?W6qwm,?L
development of new load and resistance factor design (LRFD) specifications and commentary P@LFX[HtM
for the seismic design of bridges. The research considered design philosophy nTG @=C #
and performance criteria, seismic loads and site effects, analysis and modeling, and !xqy6 %p
design requirements. The specifications are nationally applicable with provisions for S-^:p5{r
all seismic zones and are intended to be integrated into the AASHTO LRFD Bridge -'q#u C
Design Specifications. Bf)}g4nYn
The research was performed by a joint venture of the Applied Technology Council 8ClOd <I
and the Multidisciplinary Center for Earthquake Engineering Research. The report Z4&,KrV
fully documents the methodology used to develop the recommended specifications. z' oK
0"
The recommended specifications provided the technical basis for a stand-alone set of u
ZzO$e
provisions prepared by the ATC/MCEER Joint Venture titled “Recommended LRFD ] 2Vu+AP
Guidelines for the Seismic Design of Highway Bridges.” AASHTO will consider these H K]-QTEn
provisions for adoption as a Guide Specification in 2002.
