Similarity Research on the Action of a Centrifuge Scaled Near-Field Underwater Explosion on a Concrete Gravity Dam

Concrete gravity dams are a common form of dams. The dynamic response analysis of concrete gravity dams under the action of underwater explosions is indispensable for survivability assessments. Due to the constraints of the environment and other conditions, an underwater explosion test of a prototype concrete gravity dam is difficult to achieve. The centrifuge scaled-down test that satisfies similarity theory provides a new way to study the dynamic response of underwater explosions on concrete gravity dams. In a near-field explosion, the shock wave of an underwater explosion will cause direct damage to the gravity dam, and the detonation products after the shock wave will aggravate the damage. Under the premise of verifying the concrete dynamic response material parameters and the fluid–solid coupling model of the underwater explosion, numerical calculations of the scaled underwater explosion model of the centrifuge and the prototype underwater explosion were carried out, and the similarity between the scaled dam response model of the underwater explosion centrifuge and the prototype was discussed. The analysis shows that the scaled-down centrifuge model can better reflect the local damage of the prototype dam subjected to shock waves. The difference between the scaled centrifuge model and the prototype model of underwater explosion damage to the dam is concentrated on the overall damage. The damage effect of detonation products on the prototype dam body is mainly concentrated in the middle and lower parts of the dam body, while the damage effect of detonation products on the dam body in the scaled-down model is mainly concentrated in the middle and upper parts of the dam body.