Wedge Movement Effects on the Nonlinear Behavior of an Arch Dam Subjected to Seismic Loading

Arch dam abutment stability is regarded as a prominent part of designing concrete dams. In the present study, the seismic stability of the rock wedges in the foundation of the concrete arch dams is studied using limit state and finite-element methods. For this purpose, a double-curvature arch dam (the Bakhtiari dam), is taken into consideration. Each abutment has six wedges. The finite-element model (FEM) includes the dam, reservoir, wedges, and the rest of the foundation. The dam abutment seismic safety is analyzed using the time history analysis along with the Londe method. Subsequently, the wedges in the proximity of the critical state are identified. Afterward, the analysis of the critical wedges’ joints has been conducted via FEM, and the damage propagation in the dam body has been investigated. Moreover, the effects of the grout curtain efficiency, hazard level, and foundation flexibility on the nonlinear behavior of the arch dam with integrated foundation and foundation with joints are scrutinized. The outcomes reveal the remarkable effect of joints considered in the foundation on the dam behavior.