The comparison of soil-pile interaction and fixed base support for integral prestressed concrete box-girder bridge

Abstract

This paper is to investigate the effect of soil-pile interaction for integral prestressed concrete box-girder bridge under low intensity earthquake. The soil-pile interaction was compared to fixed base support to see its effect. In this case study, one integral prestressed concrete box-girder bridge in Selangor, Malaysia had been chosen, that is, Kampung Sawah Bridge. To produce the low seismic loading, the ground response analysis had been conducted to produce three synthetic acceleration time histories loading. For soil-pile interaction, the p-y curves were determined by using LPILE program. The seismic analyses conducted were vibration analysis and nonlinear time history analysis. Free vibration analysis presented the periods and mode shapes of the structure while nonlinear time history analyses presented the maximum displacement at the top of pier and middle of deck and pier and deck forces response. It can be concluded that the soil-pile interaction support gives the longer period compared to fixed base support which almost differ about more than five times higher for the first mode. The displacement soil-pile interaction is higher compared to fixed base support; the increasing of displacement is more at transverse direction event for deck and pier. The all forces response from soil-pile interaction support is higher compared to fixed base support, except the axial force response of pier. Key words: Nonlinear time history, integral concrete box-girder bridge, soil-pile interaction, fixed base.