The Earthquake Engineering Online Archive

Nonlinear soil-structure interaction of skew highway bridges

Chen, Ma-Chi; Penzien, Joseph

UCB/EERC-77/24, Earthquake Engineering Research Center, University of California, Berkeley, 1977-08, 127 pages (535/C48/1977)

This report is one in a series to result from the study "An Investigation of the Effectiveness of Existing Bridge Design Methodology in Providing Adequate Structural Resistance to seismic Distrubances," sponsored by the U.S. Dept. of Transportation, Federal Highway Admin. Descriptions are given of the analytical investigations of the seismic response of skew highway bridges where soil-structure interaction effects are important. Four different mathematical model elements are incorporated into the three-dimensional computer program which possesses the capability of performing linear or nonlinear time-history dynamic response analysis. Solid finite element modeling is used for the backfill soils and the abutment walls. The bridge deck, pier columns, and pier caps are modeled using prismatic beam elements. A frictional element is used to model the discontinuous behavior at the interfaces of the backfill soils and abutments. Boundary elements provide foundation flexibility at the base of columns supported on either piles or spread footings. In the nonlinear mathematical model, the effects of separation, impact, and slippage at the interfaces between the abutment walls and the backfill soils are taken into consideration. Computational efficiency is achieved through the use of mathematical techniques including matrix reduction procedures, iteration procedures, and variable time steps. A number of analytical solutions are carried out considering a skewed three-span bridge with backfill soils. Different mathematical models are used to study the parameters which may influence the seismic response of the bridge. Finally, conclusions are deduced from the analytical results.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-77-24.pdf (33 MB)