预置裂纹靶板在水下冲击波作用下的动态响应研究

舰船结构在生产和使用过程中不可避免地会出现划痕、凹槽等损伤，使结构的水下抗毁伤性能出现不同程度的降低。利用非药式等效水下冲击加载装置，对预置裂纹靶板进行了水下冲击加载实验，通过高速相机对靶板变形进行记录；结合ABAQUS仿真软件对加载实验进行计算，对预置裂纹靶板在水下冲击载荷作用下的动态响应机制进行研究，得出了“3阶段”动态响应现象结论；对不同预置裂纹形状靶板进行研究，发现不同预置裂纹形状靶板的动态响应差别在于最终破坏阶段，靶板破坏倾向于出现最少裂缝情况下，将能量全部释放。对裂纹参数进行研究，结果表明：预置裂纹靶板离面位移与载荷冲量近似呈线性关系，随着裂纹深度和长度的增长，结构剩余冲击强度不断下降。

Research on Dynamic Response of Pre-cracked Target Plate Subjected to Underwater Shock Wave

The ship structure is inevitable to be scratched, grooved or damaged in the processes of manufacturing and use, which may reduce the damage-resistant capability of ship structure to some extend. An equivalent underwater explosion impact loading device was used for the impact experiments on the pre-cracked target plate, and the deformation of target plate was recorded by using high-speed camera. The dynamic response mechanism of the pre-cracked plate under underwater impact load was studied through experiment and ABAQUS simulations, and the “three-stage” dynamic response result was acquired. The results show that the dynamic responses of target plates which have pre-cracks with different shapes are different in the final failure stage. The target plates tend to release all the energy with fewest cracks. The crack parameters are studied. The displacement of pre-cracked target plate has approximately linear relationship with the loading impulse. With the increase in the crack depth or length, the residual impact resistance of target plate decreases.Key