含张开单裂隙砂岩破裂过程围压效应的数值模拟

为研究不同倾角裂隙砂岩试样在压缩过程中的围压效应,以室内单轴压缩试验结果标定岩体细观参数,采用改进刚体弹簧元法对不同倾角裂隙试样在不同围压下的破坏过程进行模拟。基于模拟结果,研究了围压对岩样强度、破坏模式及微裂纹发育特征的影响。结果表明,裂隙砂岩试样在压缩过程中具有明显的围压效应,相同裂隙倾角试样,其峰值强度、残余强度、弹性模量和变形模量均表现出随围压增加而增加的规律;不同围压作用下,不同倾角裂隙试样内部微裂纹演化规律相似,且其最终破坏形态均表现出以剪切破坏为主的破裂方式。

Numerical Simulation of Confining Pressure Effect in Failure Process of Sandstone Containing Single Open Fissure

In order to study the effect of confining pressure of jointed rock with different fissure angles under compression process, a set of micro-parameters were calibrated by uniaxial compression laboratory experiment results, a modified rigid body spring method (RBSM) was proposed to simulate the failure process of fissured rock with different fissure angle under different confining pressure. On the basis of the simulated results, the influences of confining pressure on strength characteristic, failure mode and crack propagation were analyzed in detail. Results show that confining pressure has a significant effect on the process of compression of fissured rock, and the peak strength, residual strength, elastic modulus and deformation modulus of fissured rock increase with the increase of confining pressure. The evolution laws of micro cracks in the specimens with different fissure angles under different confining pressure are similar, and the ultimate failure modes of all specimens mainly exhibit shear rupture damage.