A 3-D boundary element model for the dynamic analysis of arch dams with porous sediments

Abstract

A three-dimensional boundary element technique for dynamic analysis of arch dams including dynamic interaction and sediments on the bottom of the reservoir is presented. The dam and the foundation rock are assumed to be viscoelastic domains with linear behaviour. The water is assumed to be compressible and the sediment is considered as a two-phase poroelastic material according to Biot's theory. The four domains (dam, foundation rock, water and bottom sediments) are discretized and the interaction between them is rigorously represented. The effects of sediments on the dynamic response of arch dams are evaluated for rigid and compliant foundation. Upstream, vertical and cross-stream excitation are considered. The influence of the degree of saturation of the sediment is analysed. Other modelling of the sediment as a single-phase scalar medium are considered in order to reduce the degrees of freedom of the system.