Numerical simulation analysis of damage mode of concrete gravity dam under close-in explosion

The study of damage mode of a concrete gravity dam under close-in explosive impact is a critical issue to assess the dam’s antiknock security. In this paper, a fluid-structure coupled finite element numerical method with combination of Lagrangian and Eulerian algorithm is applied, taking into consideration the damage development process of the Huangdeng concrete gravity dam. The damage mode of a square reinforced concrete slab under close-in blast loads has been simulated and discussed as a comparison with real experiment to verify the feasibility of the numerical simulation. The influence of the presence of spillway tunnel on damage mode of the concrete gravity dam has been investigated. Different damage modes of the concrete gravity dam are compared and studied for different standoff distances and different detonation depths. The damage process of the dam with time course is researched. The influence of different mediums, where the explosion occurs, on the failure mode of the dam is also researched. The analysis results show that attention should be paid to the concrete gravity dam subjected to close-in upstream shallow underwater blasts. It also should be focused on that the presence of spillway tunnel can affect the damage result of the dam.