Blast resistance of concrete gravity dams subjected to underwater contact explosion with different protective measures
Aobo Liu, Gaohui Wang, Wenbo Lu, Ming Chen, Peng Yan
Abstract
High dams are susceptible to underwater explosions in warfare nowadays due to their important value, so it is necessary to explore protective measures to improve the blast performance of dams. Considering the limited research on antiknock measures for dams, this paper aims to study the anti-explosion effects of different protective measures on the gravity dam subjected to underwater contact explosion. The concrete damaged plasticity model is utilized to simulate the properties of concrete , and the coupled Euler-Lagrange method is used for the dynamic coupling process. Initially, the effects of the upstream concrete protective layer with different strengths in the dam on shock wave propagation, damage characteristics, and dynamic responses of the dam are analyzed and compared. On this basis, the blast resistance of the dam with the upstream layer considering various structural traits is further discussed. Finally, the protective measures for some vulnerable parts of the dam such as the dam heel and the downstream slope change are explored. The results show that the wave impedance of the protective layer concrete affects its blast resistance. The high-strength concrete layer has little effect on the blast resistance of the dam, while the asphalt concrete layer has a significant impact on improving the anti-explosion performance of dams for its low elastic modulus and strength. Additionally, the local asphalt concrete layer near the explosion source on the upstream face of the dam can obtain enough protection effects. It is also concluded that local protection at the downstream slope change with high-strength concrete or steel bars can reduce its damage degree. The key-wall set at the dam heel can decrease the crack length at the foundation.