Effect of dynamic soil-structure interaction modeling assumptions on the calculated seismic response of railway bridges with single-column piers resting on shallow foundations.

In this study, the effect of dynamic soil-structure modelling assumptions on the calculated seismic response of railway bridges with single column piers resting on shallow foundations is investigated. For this purpose, 10 structural models of a typical railway bridge are built in decreasing levels of complexity, starting from the most complicated model with nonlinear elements to accurately simulate dynamic soil-structure interaction. Then, the structural model is gradually simplified to a level where the effects of foundation-soil and abutment-backfill interactions are totally eliminated. Nonlinear time history analyses of the structural models are conducted with a set of ground motions with various intensities representing small, medium and large intensity earthquakes. Analyses results revealed that removing the abutments from the structural model results in significant discrepancies in the longitudinal direction response of the bridge but has negligible effect in the transverse direction. Furthermore, analyses results show good correlation between the complex and simplified models in deck displacement and bearing displacement but notable differences are observed in substructure responses when the soil-structure interaction is neglected. Therefore, at least linear soil-structure interaction modeling should be considered in the analyses for correct estimation of the substructure responses. • Effect of soil-structure modelling assumptions on the seismic response of bridges resting on shallow foundations is outlined. • Effect of including and excluding the abutments from the structural model on the seismic response of bridges is outlined. • The effect of radiation damping and equivalent hysteretic damping on the seismic response ofbridges is presented. • Information on structural modeling of bridges for seismic analyses is provided. [ABSTRACT FROM AUTHOR]