Numerical Investigation into Hydrodynamic Effects on the Seismic Response of Complex Hollow Bridge Pier Submerged in Reservoir: Case Study

Abstract

Hydrodynamic effects are concerns in the seismic analysis of bridges with complex hollow piers submerged in a reservoir. In this study, potential-based fluid elements were employed to set up a three-dimensional numerical fluid–structure interaction model to account for the hydrodynamic effects of interest. A typical reservoir bridge with a nonuniform hollow pier was taken as an example structure. Linear and nonlinear dynamic analyses were carried out to investigate the seismic responses of the example pier under six near-fault and six far-field earthquake records. The accuracy of the added-mass model was validated in the linear and nonlinear domains. It can be concluded from the case studies that (1) the effect of surface gravity waves is not significant; (2) the inner water increases the seismic responses of the hollow pier; (3) structural nonlinearity cannot be neglected in seismic analyses of piers subjected to strong earthquakes, especially for near-fault earthquakes; and (4) the added-mass model is an efficient alternative method for both linear and nonlinear seismic analyses, regardless of water depth, earthquake characteristics (e.g., near-fault or far-field), and intensity.