节理频度对类岩石介质裂纹扩展行为的影响

为研究节理频度对类岩石介质受冲击荷载作用时动态裂纹扩展行为的影响,借助新型数字激光动态焦散线实验系统进行了试验研究.结果表明:随着节理频度的增大,竖向裂纹起裂时的动态应力强度因子减小,但大于水平节理翼侧裂纹起裂时的应力强度因子;裂纹扩展至节理区域时,动态应力强度因子有一个交替震荡的过程,此过程持续时间随节理频度增大而延长;竖向裂纹从加载到起裂时间并不明显改变,但从起裂到试件贯通破坏的时间近似线性增长;竖向裂纹起裂后的速度随节理频度增大有所减小,但大于裂纹扩展通过节理区域后的速度.可见不同节理频度类岩石介质的裂纹扩展行为存在差异,为冲击荷载下岩石断裂破坏提供理论参考.

Effect of Joint Frequency on Crack Propagation Behavior of Rock-like Media

Abstract] In order to study the effect of joint frequency on the dynamic crack propagation behavior of rock-like media under impact loading, a new digital laser dynamic caustics experiment system was used for experimental research. The results show that as the joint frequency increases, the dynamic stress intensity factor decreases during vertical crack initiation, but is greater than the stress intensity factor during horizontal crack initiation of wing-side cracks; When cracks propagate into the joint area, the dynamic stress intensity factor has an alternating oscillation process, The duration of this process increases with joint frequency; The crack initiation time does not change significantly, but the time from crack initiation to specimen penetration failure increases approximately linearly; the speed after vertical crack initiation decreases with the increasing of joint frequency, but is greater than the speed of crack propagation through the joint area. It is concluded that there are differences in crack propagation behavior of rock-like media with different joint frequencies, which provides a theoretical reference for rock fracture failure under impact loading.