高渗压条件下裂隙岩体的劈裂破坏特性

基于岩体工程中普遍存在节理裂隙岩体,裂隙岩体在地下工程卸荷扰动后形成复杂应力状态和高水头压力的共同作用下将发生压剪复合破坏或拉剪复合破坏,对裂纹面的应力状态进行分析以判定其破坏模式,并进一步研究岩体裂纹开裂特性及岩桥断裂贯通力学机理,建立相应的临界水压和初裂强度判据。同时,对处于水力劈裂状态的高水头压力隧洞围岩的破坏特性进行模拟。研究结果表明:隧洞在高渗透水压的驱动下周边围岩开始发生水力劈裂,形成拉剪劈裂区;随着内水外渗的发展,随即在拉剪劈裂区外侧形成压剪劈裂带,同时,拉剪区和压剪区继续扩展直至渗流衰减趋于稳定。

Splitting failure properties of fractured rock under high water pressure

Based on the fact that fractured rock mass is prevalent in rock engineering,the fractured rock mass disturbanced in the underground after unloading will be in a complex stress states,which will cause compression failure or tension shear failure under the high water pressure,its failure mode by the stress state of the crack was determined based on the principle of rock fracture mechanics,then the cracking characteristics at the crack tip and the fracture mechanics of rock bridge were studied,and the corresponding value of the critical pressure and the splitting tensile strength values of the crack were determined.The damage characteristics of the surrounding fracturing rock in the high water pressure with simulation was studied.The results show that the tunnel surrounding rock driven by the penetration of high water pressure begins to have hydraulic fracturing,and forms a tensile shear splitting area with the development of water leakage.The compression zone outside of the splitting tensile area is immediately formed,and then the tensile shear zones and compression zone continue to expand until the pressure flow attenuation is stable.