单一闭合中心裂隙对岩石单轴压缩破坏特征的影响

利用颗粒流软件模拟了含单一闭合中心裂隙岩石的单轴压缩数值试验,分析了裂隙宽度、闭合裂隙长度、摩擦系数和倾角对裂隙岩石破坏特征的影响。结果显示裂隙闭合与否对裂隙岩石的强度和破坏特征存在影响;裂隙长度越小,裂隙摩擦系数越大,裂隙倾角越接近于0°或者90°时,裂隙岩石破坏特征越接近于完整岩石状态。翼型裂纹和次生裂纹的扩展形成了岩石的贯通破坏面,其中翼型裂纹表现为Ⅰ型断裂扩展形成贯通破坏面,次生裂纹表现为Ⅱ-Ⅰ型断裂扩展形成贯通破坏面。

Effect of Single Closed Central Fissure on Failure Characteristics of Cracked Rock under Uniaxial Compression

Particle flow code was used to simulate uniaxial compression test of rock containing one closed central pre-existing fissure. The effects of fissure width, fissure length, friction coefficient and dip angle on the failure characteristics of cracked rock were analyzed. Results show that crack closure has impact on the strength and failure characteristics of cracked rocks. With the decrease of fissure length or increase of fissure's friction coefficient or the decrease of dip angle to zero or the increase of dip angle to 90°, the failure characteristic of cracked rock is more similar to that of intact rock. Extension of wing cracks and secondary cracks forms the macroscopic failure plane of rock. Mode-I fracture extension of wing cracks forms the macroscopic failure plane of rock while mode Ⅱ-Ⅰ fracture extension of secondary cracks forms the macroscopic failure plane of rock.