In order to study the mechanism of the interaction between the stationary crack and the moving crack,the impact experiments of the pre-cracks with different length were carried out by a digital-laser dynamic caustics test system.Experimental results show that the initiation stress intensity factor and the initiation time of the vertical main crack decrease with horizontal main crack length.The longer the horizontal main crack length,the easier the vertical main crack initiation.During the vertical main crack propagating towards the horizontal main crack,the mean value of the stress intensity factor of the wing crack and the peak value and the mean value of wing crack propagation velocity decrease with horizontal main crack length.After the wing crack and the vertical main crack coalescence,stagnation time and the initiation stress intensity factor of the vertical main crack first decreases and then increases with vertical main crack length.%为了研究静止裂纹与运动裂纹相互作用机制,采用数字激光动焦散系统进行了含不同长度预制裂纹的冲击试验.试验结果表明:竖向主裂纹起裂时的应力强度因子和起裂时间均随水平主裂纹长度增加逐渐减小,水平主裂纹长度越长竖向主裂纹更易起裂;竖向主裂纹朝水平主裂纹扩展阶段,其翼裂纹的应力强度因子均值和扩展速度峰值、均值均随着水平主裂纹长度增加而降低;翼裂纹与水平主裂纹汇聚后,在水平主裂纹停滞的时间和水平主裂纹起裂时的应力强度因子均随着水平主裂纹长度增加呈现先减小后增大趋势.
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