nchrp472 *+-}P|S:
Recent damaging earthquakes in the United States and abroad have demonstrated V^JV4 `o
the earthquake vulnerability of highway bridges that were designed to existing seismic z54EG:x.7^
codes. To address this inadequate performance, extensive research programs have been ~p1j`r;
carried out. These programs have advanced the state of the art to the point where a new Z3{>yYR+
specification for seismic design is necessary to take advantage of new insight into ]%|GmtqZs,
ground motion and geotechnical effects, improved performance criteria, and more lp<g \
advanced analytical and design methodologies. ~Q?a|m V,
The objective of this research was to enhance safety and economy through the ]vgB4~4#LP
development of new load and resistance factor design (LRFD) specifications and commentary WOQP$D9
for the seismic design of bridges. The research considered design philosophy ;ado0-VQi'
and performance criteria, seismic loads and site effects, analysis and modeling, and nN*w~f"
design requirements. The specifications are nationally applicable with provisions for
Jd %H2`
all seismic zones and are intended to be integrated into the AASHTO LRFD Bridge {k>Ca
Design Specifications. Fz1_w$^
The research was performed by a joint venture of the Applied Technology Council vY%d
and the Multidisciplinary Center for Earthquake Engineering Research. The report y=`2\L" O
fully documents the methodology used to develop the recommended specifications. VTG9$rQZ
The recommended specifications provided the technical basis for a stand-alone set of N$h{Yvbn
provisions prepared by the ATC/MCEER Joint Venture titled “Recommended LRFD n;( \5{a
Guidelines for the Seismic Design of Highway Bridges.” AASHTO will consider these "]z-: \ V
provisions for adoption as a Guide Specification in 2002.
