Nonlinear seismic response of concrete gravity dams using damage mechanics including dam-reservoir interaction

摘要

A local anisotropic damage mechanics model based on energy equivalence was used for evaluating the nonlinear static and dynamic response of concrete gravity dams. The cracks within the elements was formulated as coaxial rotating cracks and the effect of hydrody-namic pressure was included using the staggered displacement method. The features of strain rate effects; strain softening and closing/reopening of cracks were included in the model. The mesh objectivity of the nonlinear model was satisfied by the fracture energy conservation technique. The Pine Flat dam was chosen to investigate the performance of the proposed algorithms. It was found that the resulted crack profiles when including dam-reservoir interaction is less diffused in comparison when the reservoir is modeled as added mass and also there is not any numerical instability during dynamic analysis.