nchrp472 $Ome]+0
Recent damaging earthquakes in the United States and abroad have demonstrated YR%iZ"`*+O
the earthquake vulnerability of highway bridges that were designed to existing seismic +iVEA(0&$
codes. To address this inadequate performance, extensive research programs have been p3Sh%=HE'
carried out. These programs have advanced the state of the art to the point where a new N[%u>!
specification for seismic design is necessary to take advantage of new insight into w5@ 5" M
ground motion and geotechnical effects, improved performance criteria, and more wPA^nZ^}9c
advanced analytical and design methodologies. nhV"V`|d
The objective of this research was to enhance safety and economy through the k3~9;Z
development of new load and resistance factor design (LRFD) specifications and commentary C|'DKT4M&
for the seismic design of bridges. The research considered design philosophy (eHyas %X
and performance criteria, seismic loads and site effects, analysis and modeling, and ] lB zp D
design requirements. The specifications are nationally applicable with provisions for TdtV (
all seismic zones and are intended to be integrated into the AASHTO LRFD Bridge *ByHTd
Design Specifications. xoaO=7\io
The research was performed by a joint venture of the Applied Technology Council dmFn0J -\
and the Multidisciplinary Center for Earthquake Engineering Research. The report N]<(cG&p
fully documents the methodology used to develop the recommended specifications. $3-v W{<
The recommended specifications provided the technical basis for a stand-alone set of _plK(g-1J%
provisions prepared by the ATC/MCEER Joint Venture titled “Recommended LRFD !l:GrT8J
Guidelines for the Seismic Design of Highway Bridges.” AASHTO will consider these ZnG.::&:
provisions for adoption as a Guide Specification in 2002.
