基于FLAC3D的层状岩石强度特征研究

利用单元切割法确定节理单元并赋予相应的本构模型进行计算,研究单轴与不同围压条件下的不同节理倾角层状岩石的力学特性。结果表明,无论是单轴压缩试验还是三轴压缩试验,节理对岩石强度的影响都很显著; 随着节理倾角增加,层状岩石单轴抗压强度先减小后增大,呈U型分布,在层理倾角呈60°时,抗压强度值最低; 从塑性单元个数可以看出,层理倾角0°~30°以及90°时,岩石以突然破坏为主,而层理倾角45°~75°时岩石破坏较缓慢; 随着围压增加,岩石抗压强度增加,岩石破坏时间延后,弹性段增长。研究结果可为岩石、岩体的各向异性问题的研究提供参考。

Probe into Strength Characteristics of Layered Rock Based on FLAC3D

A cutting unit method was used to determine joint unit and constitutive model for computation. And mechanical properties of layered rock with different joint inclination angle under uniaxial and different surrounding rock pressure were studied. Either uniaxial or triaxial compression tests showed joint could bring remarkable influence on rock strength. As the joint inclination angle increased, the uniaxial compressive strength of layered rock turned to be increased after an initial decrease, presenting a U-curve in the distribution. And the compressive strength reached the minimum value with the joint inclination angle at 60°. The number of plastic units showed that the most of rock failure were suddenly occurred with the joint inclination angle within the range of 0°~30° and at 90°, while the rock failure was developed slowly with the inclination angle within the range of 45°~75°. With the increasing of surrounding rock pressure, the compressive strength of rock increased, the time for rock failure was prolonged and the elastic segment also became longer. These results can be of reference for the study on anisotropy problem of rock or rock mass.