A discrete crack joint model for nonlinear dynamic analysis of concrete arch dam

Abstract

Concrete arch dams are generally constructed of massive plain concrete with almost no tensile resistance. To control tensile forces due to concrete shrinkage, temperature variations and for construction facilitation, arch dams are built in cantilever monoliths separated by vertical contraction joints. Earlier studies show that the modeling of such joints has significant influence on the seismic safety evaluation of arch dams. This fact is due to the tensile and shear failures of joints causing a redistribution of internal forces during and after a big earthquake. In the present study, a nonlinear joint element model with a coupled shear–tensile behavior for realistic finite element analysis of dam–reservoir system is presented. Reservoir upstream radiation, and bottom partial absorption of acoustic waves, as well as water compressibility are considered. The model when applied to simpler cases solved by other workers shows good performances. However, it is much more useful to solve problems not considered so far, e.g., shear keys behavior, joint damages, etc. The model could be employed effectively and conveniently for earthquake safety evaluation of arch dams in highly active seismic regions.