The Earthquake Engineering Online Archive

Analytical investigations of seismic response of short, single, or multiple-span highway bridges

Chen, Ma-Chi; Penzien, Joseph

UCB/EERC-75/04, Earthquake Engineering Research Center, University of California, Berkeley, 1975-01, 183 pages (555.6/C475/1975)

This report is the third 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 Disturbances," sponsored by the U.S. Dept. of Transportation, Federal Highway Admin. Descriptions are given of the analytical investigations of the seismic response of short, single or multiple-span highway bridges of the type where soil-structure interaction effects are important. Six different mathematical model elements are incorporated into the computer program which possesses the capability of performing linear or nonlinear analyses. Finite element modelling is used for the backfill soils. Bridge deck, piers, and abutments are modelled using prismatic beam elements. A frictional element is used to model the discontinuous behavior at the interface of backfill soils and abutments. Discontinuous-type expansion joint elements are also included. Linear spring elements provide flexibility at the vertical soil boundaries. The soil foundation flexibilities under columns are established using elastic halfspace theory. In the nonlinear mathematical model, the effects of separation and impact at the interface between abutments and backfills, the yielding at concrete columns and backfill soils and slippage at the expansion joints are taken into consideration. Parameter studies are first carried out considering a rigid wall backfill soil system. A short, stiff, three-span bridge is then investigated with full soil-structure interaction effects included. Finally, based on the analytical results, a general conclusion regarding the capability of the analyses is deduced.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-75-04.pdf (9 MB)