基于三维数字图像相关方法的水下冲击载荷作用下铝板动力学响应研究

基于数字图像相关（DIC）方法搭建了三维动态 DIC方法测试系统，利用冲击加载实验设备，对喷涂散斑的铝靶板进行冲击加载实验，获得了靶板的实时离面位移场；并利用安装在水靶舱壁面的压力传感器，测取了水中冲击波压力时程曲线；建立了针对冲击实验的二维轴对称仿真模型，分析了水靶舱内冲击波的形成与传播过程以及靶板的动态响应变形进程。研究结果表明，靶板的变形是由边界向中心呈环形扩展的，而且靶板极容易在法兰约束边界处出现剪裂现象。靶板实时变形与测点压力时程的实验值与仿真值具有良好的一致性，这表明结合三维动态DIC方法测试系统与等效加载设备可以实现对结构的水下冲击响应分析研究工作。

Dynamics Analysis of AL Plate Subjected to Underwater Impulsive Loads Based on 3D DIC

A three-dimensional dynamic digital image correlation (DIC) test system is set up based on the digital image correlation(DIC) method. The dynamic response experiment of AL1060 plate with speckles is conducted using the underwater impact loading device, and the out-of-plane displacement of Al target is obtained. The pressure-time histories of shock wave are measured by dynamic high-pressure transducers mounted on an anvil. A two-dimensional axisymmetric simulation model is established, and the formation and propagation of shock wave in water and the deformation process of Al plate are analyzed. The investigation shows that the deformation growth of the target presents an annulus expanding from the boundary to the center, and a shear cracking phenomenon easily appears at the constraint boundary. The calculated real-time deformation of target and the shock wave-pressure history are well in agreement with the experimental data，which confirms that it is feasible to study the underwater shock of plate structure using the underwater impact loading device in combination with 3D DIC.