基于PFC2D的泥质灰岩软弱夹层结构面直剪试验颗粒流模拟分析

PARTICLE FLOW MICRO AND MACRO ANALYSIS OF ARGILLACEOUS LIMESTONE INTERLAYER STRUCTURE DIRECT SHEAR TEST BASED ON PFC2D

对取自于某滑坡滑带上的泥质灰岩软弱夹层进行颗粒流PFC程序数值直剪试验模拟,并对直剪过程中结构面的力学演化机制和破坏特征进行细观方面的深入分析。分析得以下几点结论:(1)在结构面直剪开始至破坏阶段,中后部分的颗粒承受了更多的剪应力。(2)在剪切应力-位移曲线表现出塑性特征的剪切过程中,产生张拉裂纹,在此阶段裂纹急剧增加,裂纹的发展使得结构面上颗粒间的法向接触数量将明显减少,同时导致颗粒之间的接触压力显著提高,造成结构面上的张拉裂纹与剪切裂纹数量增加显著,剪切破碎带形状明显。

Using particle flow theory PFC programs to simulate weak interlayer come from a landslide, and analysis the process of the evolution mechanism and failure characteristics of the direct shear test from macro and micro view deeply. Get the following points:(1) In the shear test process, the after part of the particles bear more shear stress.(2) When stress displacement curve exhibited shear plastic characteristics in shear process, tension crack emerged, and the whole number of crack increased dramatically. With the crack development of the structural surface, the normal contact number will continue to decrease, and caused the increasing of contact pressure between particles, resulting in that the shear crack and tensile cracks along the structural surface increased, and the formation of broken shear band.