Seismic response of a large, isolated aqueduct considering fluid–structure and soil–structure interactions.

This article focuses on the seismic response analysis of a large-scale aqueduct by developing a three-dimensional fluid–structure–soil interaction model using the arbitrary Lagrangian–Eulerian (ALE) method and a dynamic Winkler foundation model. The study incorporates frictional pendulum bearings modeled as a simple pendulum and non-linear spring to evaluate their seismic isolation effect, and compares uniform and non-uniform seismic excitation models with and without pile–soil dynamic interactions. Results indicate that frictional pendulum bearings effectively isolate seismic forces even with water sloshing present, but accurate seismic response predictions require considering pile–soil–aqueduct dynamic interactions; neglecting these can lead to under- or overestimation of structural responses. The analysis also identifies potential tensile damage risks at the corners of middle piers under earthquake loading, suggesting the need to enhance concrete tensile strength in these areas for safety.