非贯通节理岩体剪切力学行为细观模拟分析

MESO-simulation Analysis of Discontinuous Jointed Rock Mass Shear Mechanical Behavior

通过引入光滑节理模型,可真实地反映剪切过程中节理岩体力学行为。采用颗粒流软件,从细观角度研究了不同连通率条件下剪切过程中裂纹扩展规律和剪裂面应力分布特征。研究结果表明:颗粒流数值模拟软件可以较好地再现和重复节理岩体直剪试验;细观数值模拟分析可得到剪切过程节理岩体剪切面应力分布情况;随连通率增大,节理岩体对应峰值强度减小,产生张拉裂纹比例降低;在剪切过程中剪应力不断变化,试样受到的水平剪切力主要由中间岩桥承担,两边节理只承担小部分剪力。

By introducing a smooth joint model,the mechanical behavior of the jointed rock mass during shearing can be truly reflected. Particle flow software was used to study the crack propagation law and shear stress distribution characteristics under different joint connectivity from a meso-perspective. The results of meso-simulation analysis show that: Particle flow numerical simulation software can well reproduce and repeat jointed rock mass direct shear test. The numerical simulation analysis of the meso-scale can obtain the stress distribution in the shear plane of jointed rock mass in shear process. With the increase of joint connectivity,the corresponding peak intensity of jointed rock mass increases,and the proportion of tensile cracks increases. In the process of shearing,the shear stress changes continuously,the horizontal shear force of the specimen is mainly borne by the intermediate rock bridge,and the joints on both sides only bear a small part of the shear force.