中文摘要：

将VG损伤模型推广到二维情况，考虑了最大主应力方向对损伤演化的影响，并使用显式断裂算法对20钢管在GI-920炸药滑移爆轰驱动下层裂的问题进行二维数值模拟。分析了一维内爆和滑移爆轰两种加载方式下作用于钢管外表面的压力及钢管内部受力状态的区别，考察了滑移爆轰加载方式下钢管外表面的受力随炸药厚度变化的规律，进而研究了钢管内损伤的分布和演化，以及裂纹的产生和扩展现象。计算得到的层裂片初始厚度随炸药厚度的变化规律与实验结果符合较好。

英文摘要：

VG（void growth） damage model is generalized to the 2D situations, which counts in the effect of the principal stress direction on the evolution of damage, and is used in the 2D numerical simulations of spallation of steel tube driven by sliding detonation of high explosive GI-920, as well as the explicit fracture algorithm. The different pressure profiles on the outer surface of steel tube between the 1D implosion case and the 2D sliding detonation case are analyzed. Especially the influence of the thickness of high explosive on the pressure profiles is investigated in detail. The numerical results present the distribution and evolution of damage in the steel tube, as well as the initialization and extending of the spalled crack. The initial thicknesses of spalled layer obtained numerically conform to the experiments.