Pulvino and peripheral joint eects on static and seismic safety of concrete arch dams

One of the methods in limiting tensile stresses in arch dams and removing stress concentrations at the dam-foundation interface is setting the dam body on a concrete saddle called a Pulvino. In the present study, the eects of Pulvino and peripheral joints on the static behavior and seismic performance of arch dams are investigated. Dez Dam with a height of 203 m was selected as a case study and all contraction joints of the dam body were modeled using the discrete crack approach based on as-built drawings. Also, the surrounding rock was modeled as a mass-less medium tied to Pulvino. The dam-reservoirfoundation system was analyzed under static loads accounting for stage construction eects, hydrostatic and thermal loads. The provided numerical model was then excited using nearand far-eld earthquake ground motion. It was found that modeling the peripheral joint between the saddle and the main dam body changes the direction of principal stresses and their distribution patterns, and the safety of the system is improved. In addition, over stressed surfaces on the faces of the dam body decreased in comparison with the model without a peripheral joint.