Effect of Contraction Joints on Earthquake Response of an Arch Dam

The modeling and dynamic analysis of a concrete arch dam, the impounded water, and the foundation rock is an important step in the earthquake‐safety evaluation of the system. An analysis assuming the dam is a monolithic structure often shows large tensile stresses in the arch direction. Arch dams are generally constructed as cantilever monoliths, however, and the joints between the monoliths cannot develop the tensile stress predicted from a linear analysis. The joints are expected to open during an earthquake, releasing the arch stresses and redistributing forces. In this study, a nonlinear element is developed to model the opening and closing of contraction joints. The joint elements are combined with linear shell, solid, and fluid finite elements to model an arch dam system. The assumption that the monoliths are linear substructures significantly reduces the computation required to solve the nonlinear equations of motion. The earthquake analysis of a typical concrete arch dam shows the importance of co...