A new impact factor considering structural morphology for concrete gravity dams subjected to underwater non-contact explosion

Abstract

The impact factor has a promising prospect in the prediction and assessment of shock wave induced damage to structures under underwater explosion. However, the existing impact factors are not applicable to variable cross section structures because there is no consideration of the geometry effect of the target structure. In this paper, a new type of underwater explosion impact factor, which can comprehensively consider the effects of detonation position, interface reflection, and geometric properties of target structures, is proposed. To verify the effectiveness of the impact factor proposed in this paper, an explosion model test is carried out and the reliability of the numerical simulation method is verified by comparing the numerical simulation results with the test results; a concrete gravity dam was taken as the research object, the damage to the dam subjected to various underwater explosion attack conditions is obtained by numerical simulation; through the analysis of mathematical relationship between the impact factor and the damage range, the effectiveness of the proposed impact factor is discussed, and the damage predicted effect of four different impact factors is also compared. The research shows that the impact factor proposed in this paper can accurately predict the local damage of the concrete structure under underwater explosion, combined with the damage classification criterion, can quickly obtain the damage level of the structure to underwater explosion.