LAUSR

Abstract In order to meet the demand for power, irrigation, flood control, drinking water, etc., many orifices are usually designed on the dam body. This paper is aimed to evaluate the close proximity underwater explosion effects on the nonlinear dynamic response of concrete gravity dams with orifices. The accuracy and reliability of the coupled model is calibrated against a previous experimental test. The effects of the existing orifice on the damage processes of concrete gravity dams to close proximity underwater explosion are investigated. Damage characteristics of gravity dams with the orifice under close-in, inlet and internal underwater explosions are compared. The influence of the reinforcement and the water inside the existing orifice on the nonlinear dynamic response of concrete gravity dams is also discussed. The results show that the dam with orifice suffers more serious damage subjected to close proximity underwater explosion than the dam without orifice. Closing the gate of the orifice will significantly reduce the damage level of the dam.