A coupled study of soil-abutment-superstructure interaction

This paper presents a coupled numerical modelling of the soil-structure interaction for a multi-span girder bridge, inspired by a case study in Italy, to analyse the importance of the local dynamic response of the abutments in the seismic performance of the bridge. The full soil-bridge model was implemented in the analysis framework OpenSees, describing the mechanical behaviour of the foundation soils by means of an advanced constitutive model calibrated against experimental data. The results of the simulations demonstrate the relevance of the inertial effects, deriving from the dynamic response of the embankment, that enhance the non-linearity in the behaviour of the soil-abutment system. The present study is part of a wider research project concerning the dynamic behaviour of bridge abutments and its effects on the global structural performance. In this view, the proposed soil-bridge representation constitutes a benchmark for the validation of simpler analysis methods, using macro-element representations for the simulation of the dynamic response of the soil-abutment system.