摘要
通过颗粒流数值模拟带预制裂隙岩样的单轴压缩破裂过程,分析2组裂隙之间的错开程度对岩样破裂过程中的裂纹扩展规律及机制的影响。结果表明,裂隙间不同错开程度的岩样中的破裂模式大致相同,主要产生剪切裂纹和张拉裂纹,两者相互贯通将岩样大致分成4块;颗粒位移方向的变化是内部裂纹萌生和扩展的直观响应;岩样在压裂过程中大致可分为弹性阶段、峰前裂纹的萌生及稳定扩展阶段、峰后裂纹快速扩展失稳阶段;压裂破坏过程中产生的总能量,一部分储存于颗粒内部,一部分散失,裂纹萌生之时恰是耗散能增加之时。
Based on the particle flow numerical simulation of uniaxial compression rupture process of prefabricated fractured rock samples, the influences of fracture dislocation degree of two sample groups on crack growth law and mechanism during rupture process are analyzed. The results show that, (a) the rupture modes of rock samples with different fracture dislocation degrees are almost the same, mainly producing shear cracks and tensile cracks, and the inter-connection of two kinds of cracks divides the rock sample into four pieces; (b) the change of particle displacement direction is the direct response of crack initiation and propagation; (c) the fracturing process of rock sample can be roughly divided into the elastic stage, the initiation and stable growth stage of pre-peak crack, and the instability stage of post-peak crack rapid expansion; and (d) the total energy produced during fracturing is partly stored in particles and partly lost, and the dissipation energy increases when the crack is formed.
引文
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