Study of the effect of stratifications on crack propagation behaviors in shale under impacting loads
WANG Xingyu1，2，ZHU Zheming1，2，QIU Hao1，2，WAN Duanying1，2，WANG Fei1，2，WANG Meng1，2
(1. MOE Key Laboratory Deep Underground Science and Engineering，Sichuan University，Chengdu，Sichuan 610065，China；
2. College of Architecture and Environment，Sichuan University，Chengdu，Sichuan 610065，China)
Abstract：In order to study the dynamic fracture characteristics and the effect of stratifications on crack porpagation behaviors in shale，the dynamic loading experiments with split Hopkinson pressure bar(SHPB) equipment were conducted on single cleavage triangle(SCT) shale specimens with different inclinations of 0°，30°，45°，60° and 90°，and the crack propagation process was simulated adopting the dynamic numerical analysis code AUTODYN by regarding shale as a composite layered material. The results show that stratifications significantly affect the crack propagation direction and the fracture morphology of the specimens. It is also revealed that the crack propagation speed correlates positively with the loading speed as a whole while that crack deceleration is likely to occur when the loading speed is lower. Cracking along the stratification plane is the main failure mode of layered rocks such as shale，but the generation of secondary cracks is not completely random. It is also found that the region of crack deceleration usually has a high probability of secondary crack initiation.
王兴渝1，2，朱哲明1，2，邱 豪1，2，万端莹1，2，王 飞1，2，王 蒙1，2. 冲击荷载下层理对页岩内裂纹扩展行为影响规律的研究[J]. 岩石力学与工程学报, 2019, 38(8): 1542-1556.
WANG Xingyu1，2，ZHU Zheming1，2，QIU Hao1，2，WAN Duanying1，2，WANG Fei1，2，WANG Meng1，2. Study of the effect of stratifications on crack propagation behaviors in shale under impacting loads. , 2019, 38(8): 1542-1556.
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2019, Vol. 38 
