A SPH-Lagrangian-Eulerian Approach for the Simulation of Concrete Gravity Dams under Combined Effects of Penetration and Explosion

The damage prediction of high dams under the attacks of earth-penetrating weapons has gained significant importance in recent years. For this purpose, a SPH-Lagrangian-Eulerian coupled approach is proposed to describe the damage processes of concrete gravity dams subjected to the combined action of the penetration and explosion. The SPH method is used to model the concrete material with the large deformation near the penetration and explosion regions. The Lagrangian algorithm is adopted to simulate the high-velocity projectile and dam body with the small distortion. And the Eulerian algorithm is employed to describe the dynamic behavior of the water and air media. The validity of the penetration model is calibrated against a previous penetration test. Meanwhile, the SPH-Lagrangian-Eulerian coupled method is verified by implementing an underwater explosion test in a concrete cube. The computed distribution of cracking damage is consistent with the result of the experimental test, which validates the validity of the proposed SPH-Lagrangian-Eulerian coupling method. Subsequently, the penetration processes of a concrete gravity dam under the high-velocity projectile are presented. After the rapid penetration, the explosives are detonated in the dam with the initial penetration damage. The shock wave propagation characteristics in the dam and reservoir water are discussed. The failure processes and dynamic responses of the dam subjected to the combined action of the penetration and explosion are investigated. The influence of the initial penetration damage and the reservoir water on the failure processes of the dam subjected to the internal blast loading is also discussed. The results show that the penetration of the high-velocity projectile only causes a local damage to the concrete gravity dam. However, the combined effects of the penetration and explosion cause significantly more damage to the upper region of the dam.