基于裂纹扩展模式的岩质斜坡阶梯状滑移破裂机制研究

发布时间：2018-04-15 00:36

本文选题：裂隙岩体 + 裂纹扩展　；参考：《岩土工程学报》2017年07期

【摘要】：阶梯状滑移破裂作为节理斜坡的一种典型破坏模式,裂隙间裂纹的扩展模式对其变形破裂机制及斜坡破裂面形态具有重要的意义。通过颗粒流程序研究了不同岩桥倾角(0°,45°,90°,135°)和围压条件下双裂隙间裂纹的贯通模式、基本特征与影响因素,揭示含双裂隙岩体在不同围压作用下裂纹扩展的细观力学机制,并推广到含多裂隙岩体裂纹扩展模式中。主要成果如下:(1)双裂隙的贯通主要通过次生共面裂纹、次生倾斜裂纹和翼裂纹;(2)裂纹扩展具有明显的围压效应,低围压条件下,裂隙的贯通主要通过翼裂纹和次生倾斜裂纹,高围压条件下,裂隙的贯通主要通过次生共面裂纹和次生倾斜裂纹;(3)裂隙的贯通应力受岩桥倾角影响较大,岩桥倾角为45°时,裂隙的贯通应力最小,裂隙最容易贯通。结合双裂隙贯通模式的研究,对多裂隙岩体贯通模式进行研究,多裂隙岩体贯通模式可以理解为多组双裂隙的贯通模式的不同组合,同时,在多裂隙贯通模式中,裂纹会寻找贯通应力最小路径扩展。最后,结合一实际斜坡案例,对阶梯状破坏斜坡的基本破裂特征进行了总结分析,并提出了相应的破裂模式分区。
[Abstract]:As a typical failure mode of jointed slopes, the crack propagation mode between cracks is of great significance to the deformation and fracture mechanism and the shape of the slope fracture surface.By means of particle flow program, the through-through model, basic characteristics and influencing factors of cracks between two fractures under different rock bridge dips (0 掳or 45 掳/ 90 掳/ 135 掳) and confining pressure are studied. The micromechanical mechanism of crack propagation in rock mass with double fractures under different confining pressures is revealed.And it is extended to the crack propagation model of multi-fractured rock mass.The main results are as follows: (1) the penetration of double fractures is mainly through secondary coplanar cracks, secondary inclined cracks and wing cracks have obvious confining pressure effects, and under low confining pressure, the cracks are mainly through wing cracks and secondary inclined cracks.Under the condition of high confining pressure, the through-through stress of fracture is mainly influenced by the inclination angle of rock bridge through secondary coplanar crack and secondary inclined crack. When the inclination angle of rock bridge is 45 掳, the penetrating stress of fracture is the least, and the fracture is the easiest.Combined with the research of the double fracture through mode, this paper studies the multifissured rock mass transfixion model, which can be understood as the different combination of the multi-group double-fracture through mode, and in the multi-fissure transfixion mode,The crack will find the minimum path propagation of the through stress.Finally, combined with an actual slope case, this paper summarizes and analyzes the basic rupture characteristics of the stepped failure slope, and puts forward the corresponding rupture mode zoning.
【作者单位】：成都理工大学地质灾害防治与地质环境保护国家重点实验室;
【基金】：国家自然科学基金项目(41130745,41272330,41572283)
【分类号】：TU45

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