Numerical analysis of bridge piers under earthquakes considering pile-soil interactions and water-pier interactions

Previous investigations have shown that both pile-soil interactions and water-pier interactions have a significant effect on the seismic performance of bridge piers. However, there is a lack of systematic research on the influence of pile-soil and water-pier interactions simultaneously on the seismic responses of real bridge piers. This study was conducted to narrow this knowledge gap through a series of numerical analysis. A simplified numerical modelling method for the soil-water-structure system was proposed and validated with results of a centrifuge shaking table test, which considered water-pier interactions by the additional mass method and pilesoil interactions by a fine finite element model. The verified numerical modelling method was used to analyse a real bridge pier under near-field and far-field earthquakes. The obtained results show that both pile-soil interaction and water-pier interaction increase the pier displacements, and internal forces of the pier decrease by pile-soil interaction and increase by water-pier interaction. The effect of water-pier interaction on the seismic responses of the pier is smaller than that of pile-soil interaction. The water-pier interaction significantly increases the bending moments of the base pier considering pile-soil interactions and shear forces of the base pier without considering pile-soil interactions.

Automated summary

This study investigated the influence of both pile-soil and water-pier interactions on the seismic responses of bridge piers. The results showed that both interactions increased the pier displacements, with pile-soil interaction decreasing the internal forces and water-pier interaction increasing the internal forces. The effect of water-pier interaction was found to be smaller than that of pile-soil interaction on the seismic responses.