软弱夹层对岩质边坡稳定性影响研究

发布时间：2018-09-08 18:48

【摘要】：本文首先分析了岩质边坡稳定性的影响因素,并总结了软弱夹层的基本特征,阐述了含软弱夹层边坡主要破坏形式以及软弱夹层对边坡的作用机理。在此基础上,将突变理论、灾变链式理论、正交试验以及数值模拟等方法运用到含软弱夹层岩质边坡的研究中。1、针对含软弱夹层岩质边坡稳定性问题,考虑软弱夹层的应变弱化和水致弱化效应,建立了含单层软弱夹层的燕尾型突变模型,根据边坡势函数形式的变化来研究边坡在滑坡演化过程中的突跳特性。2、应用灾害链理论,构建了含软弱夹层岩质边坡的灾害链,运用“孕源断链减灾”的理念,探讨了含软弱夹层岩质边坡防灾减灾的途径与对策。3、将正交试验和数值模拟相结合,选取夹层厚度、夹层倾角、夹层粘聚力、夹层内摩擦角以及夹层在边坡坡面出露处距离坡脚距离等5个因素,通过对正交设计得出的16个含软弱夹层边坡模型进行计算分析,得出每个边坡模型在X方向的最大位移值以及安全系数。最后对结果进行多因素方差分析及相关性分析,得出对边坡稳定性影响的主导因素以及相关性因素。结果表明：夹层厚度、夹层倾角以及夹层内摩擦角是边坡稳定性显著性的影响因素；软弱夹层倾角、内摩擦角以及厚度与边坡稳定性存在显著的相关关系,软弱夹层倾角越大,内摩擦角越小,厚度越大,边坡越容易发生失稳破坏。4、对软弱夹层在边坡坡面上出露与不出露两种情况分别进行数值分析,并与边坡不含软弱夹层情况进行了对比,得出几种情况下边坡变形破坏机制的不同：夹层出露时,随着出露位置靠近坡顶,变形破坏机制为滑移-拉裂→崩塌破坏；夹层不出露时,当边坡岩体岩性较好时,边坡不容易沿着夹层形成贯通的塑性变形区,边坡相对稳定。但当边坡岩体岩性较差时,边坡岩体将可能发生溃曲破坏；边坡不含软弱夹层时,边坡整体剪应变增量均匀且数值较小,边坡较为稳定。5、结合某露天矿含软弱夹层岩质边坡,对其稳定性进行研究,并提出开采过程中边坡防灾减灾的途径和措施。
[Abstract]:In this paper, the factors influencing the stability of rock slope are analyzed, and the basic characteristics of weak intercalation are summarized. The main failure forms of the slope with weak intercalation and the action mechanism of weak intercalation on the slope are expounded. On this basis, catastrophe theory, catastrophe chain theory, orthogonal test and numerical simulation are applied to the study of rock slope with weak intercalation. Considering the strain weakening and water induced weakening effect of weak intercalation, a swallowtail catastrophe model with single layer weak intercalation is established. According to the change of slope potential function form, the sudden jump characteristics of slope in the process of landslide evolution are studied, and the disaster chain theory is applied. In this paper, the disaster chain of rock slope with weak intercalation is constructed, and the method and countermeasure of disaster prevention and mitigation of rock slope with weak intercalation are discussed by using the idea of "pregnant source broken chain disaster reduction". The thickness of intercalation is selected by combining orthogonal test and numerical simulation. Five factors, such as intercalation angle, interlayer cohesion, interlayer internal friction angle and distance from the foot of the slope where the interlayer is exposed on the slope surface, are calculated and analyzed through the calculation and analysis of 16 slope models with weak intercalation, which are obtained by orthogonal design. The maximum displacement value and safety factor of each slope model in X direction are obtained. Finally, the multivariate variance analysis and correlation analysis are carried out, and the main factors and correlation factors that affect the slope stability are obtained. The results show that interlayer thickness, interlayer inclination angle and interlayer internal friction angle are the influential factors of slope stability, and weak interlayer inclination angle, internal friction angle and thickness have significant correlation with slope stability. The smaller the angle of internal friction, the greater the thickness, the more prone to failure of the slope. 4. The numerical analysis of the weak intercalation on the slope surface is carried out, and the comparison is made with the case of the slope without the weak intercalation. It is concluded that the deformation and failure mechanism of the slope is different in several cases: when the intercalation is exposed, the mechanism of deformation and failure is slip-tension crack collapse when the exposed position is near the top of the slope, and when the intercalation is not exposed, when the rock mass property of the slope is better, The slope is not easy to form the plastic deformation zone along the interlayer, and the slope is relatively stable. However, when the rock mass of the slope is poor, the rock mass of the slope may crumble and destroy. When the slope does not contain the weak intercalation, the increment of the whole shear strain of the slope is uniform and the value is small, the slope is relatively stable, and the rock slope with weak intercalation in a certain opencast mine is more stable. The stability of the slope is studied, and the ways and measures of slope disaster prevention and mitigation in mining process are put forward.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU457

【参考文献】