SEISMIC ANALYSIS OF MULTI-SPAN CONTINUOUS GIRDER BRIDGE WITH EMPHASIS ON SOIL-FOUNDATION-SUPERSTRUCTURE INTERACTION

In this paper the application of the computer program SUBSSIP-2D (Substructure method for Soil-Structure Interaction Problem: Two Dimentional Analysis) is made for the seismic analysis of a three-span continuous girder bridge on the multiple foundations of deep grouped piles and wall types. The SUBSSIP-2D is developed based on the substructure method, which first evaluates the subgrade impedance at the specified foundation nodes and the effective seismic input motions to them, and then establishes the inertial coupling between substructure and superstructure. The detail comparison is presented among solutions from various modelings and methods of analyses to derive the useful design considerations for bridges dealt with herein.