Comparative Study on Seismic Design of Highway Bridges

摘要

This paper attempts to examine the similarities and differences in the seismic design of bridges in California and China. Comparison between the Guidelines for Seismic Design of Highway Bridges (GSD) and the Caltrans Seismic Design Criteria Version 1. 3 (SDC) is conducted in three aspects, namely application of seismic design philosophy, issues of design ground motion, and evaluations of demand and capacity. It is observed that the two codes are relatively similar in the design procedures, although a significant difference can be found in the application of seismic design philosophy. The spectra defined in GSD and SDC differ greatly, and the discrepancy may reach as high as 65% under similar conditions. Requirement of lateral strength for the ductile column is assessed. In regard to ductility, the SDC sets more specific targets for the displacement demand and the ductility capacity, which seems more rational and also easier for designers to achieve.