Analytical model for time history analysis of single pier bridges considering soil–pile structure interaction effects

This study presents simplified analytical model to analyze the seismic response of typical bridge considering soil–pile structure interaction (SPSI). For this purpose, a typical bridge was selected as a case study. A 6 DOF model was developed by considering the effects of SPSI. In order to evaluate the performance of the analytical model, modal analysis of MRO bridge was first performed. According to the results, the natural period of the MRO bridge was 0.40 s. The natural period calculated in this study differs by 1.7% to 16% from other studies. Three earthquake records were then used to examine the performance of the proposed analytical model for predicting the seismic behavior of the bridge. The analytical model can predict the response of the maximum acceleration of deck up to 16% difference from that of the instrumented structure. Considering the effects of SPSI, the calculated acceleration response for bridge deck is on average 5% to 40% closer to the instrumentation data than the fixed base condition. The proposed analytical model could predict the acceleration response spectra for all three earthquakes with a relatively good approximation. Considering the effects of soil–pile structure interaction, the calculated natural period of bridge system is 10% to 40% closer to the instrumentation data than the fixed base condition.