seismic effects on Multi-span bridges with high degrees of horizontal curvature

Principle Investigators:

Dr. Ian Buckle

Dr. Ahmad Itani

Dr. David Sanders

Project Manager:

Kelly Lyttle, P.E.

Graduate Research Assistants:

M. Al-Ani (PhD), M. Levi (MS), E. Monzon (PhD), A. Saad (PhD), D. Smith, (MS) C. Wei (PhD), J. Weiser (PhD), and H. Wibowo (PhD)

Sponsored By:

National Science Foundation - NEES Shared-Use Access

Federal Highway Administration through contract DTFH61-07-C-00031

California Department of Transportation through contract 59A0695

Introduction:

A project is underway at the University of Nevada, Reno to investigate the seismic effects of multi-span curved bridges using a 2/5 scale model of a three-span bridge. The model is 145 ft long with an 80 ft radius at the centerline and it rests on four shake tables in the laboratory. The superstructure consists of three steel girders and a concrete deck that is 12 ft wide. The testing of this model is part of a larger project investigating seismic resilience, funded by the Federal Highway Administration.

The Curved Bridge Spanning All Four Shake Tables (Click to Enlarge)

Six different configurations will be tested to examine different components, including column design (with and without conventional columns), abutment design (with and without backfill behind the abutments), seismic isolation (with and without response modification devices), and the effects of live load (with and without trucks on the superstructure). This specimen was designed by a team of eight graduate students under the supervision of three professors in civil engineering.

Preliminary Testing Matrix (Click to Enlarge)

Currently, there are no design regulations on horizontally curved bridges and the data from this project will provide new insight on their behavior under seismic loading. The results of the research will be incorporated into future industry design codes. Ultimately, this will help structural engineers design curved bridges to withstand the effects of strong earthquakes.