膨胀性泥岩砂岩互层边坡崩塌机理研究

发布时间：2018-03-22 15:29

本文选题：膨胀性泥岩　切入点：互层边坡　出处：《兰州交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：受岩性差异的影响，泥岩砂岩互层边坡风化严重，再加上构造条件复杂和膨胀性泥岩特殊的工程性质，造成膨胀性泥岩砂岩互层边坡崩塌破坏模式类型复杂，国内外对膨胀性泥岩砂岩互层边坡的崩塌机理研究还不够完善。本文通过一个具体的工程实例——312国道十八里堡水库段边坡崩塌病害整治工程，研究膨胀性泥岩砂岩互层边坡崩塌的破坏机理，具体研究内容和成果如下：（1）在吸收和借鉴国内外有关边坡崩塌研究成果基础上，总结了崩塌的分类及破坏模式、崩塌的影响因素。（2）试验研究了膨胀性泥岩的物理力学性质。对泥岩试样进行了一系列的试验，重点研究泥岩膨胀力与含水率的关系，，膨胀率与上部荷载、时间、含水率的关系，通过绘制各影响因素与膨胀性能的关系曲线并对实验数据进行回归分析，分析研究各影响因素对泥岩性能的影响，得到了泥岩的物理力学参数。（3）野外勘查结合室内试验分析的泥岩工程特性，从坡体的结构特征开始，依次从崩塌的发育特征及规律、崩塌的形成条件、研究区段内的典型崩塌等方面开展研究，定性的提出膨胀性泥岩砂岩互层边坡的崩塌机理——拉裂式崩塌。（4）利用CDEM数值模拟，分析边坡在自然状况、暴雨状况、地震状况下的应力场、位移场、塑性剪应变及单元破坏情况，研究边坡三种状况下的崩塌失稳破坏机理。在考虑结构面和节理的情况下，采用基于连续介质力学的离散元方法对膨胀性泥岩砂岩互层边坡崩塌的演化过程进行再现和分析。（5）最后综合野外勘察、室内试验和数值模拟的分析结果，提出膨胀性泥岩砂岩互层边坡的崩塌机理。崩塌破坏过程可以总结为：泥岩剥落→砂岩裂隙发展→砂岩局部坠落→崩塌产生。
[Abstract]:Influenced by the difference of lithology, the interbedded mudstone slope weathered seriously, and the complicated structural conditions and the special engineering properties of expansive mudstone resulted in the complicated collapse and failure mode of the interbedded slope of expansive mudstone. The research on collapse mechanism of expansive mudstone interbedded slope at home and abroad is not perfect. The failure mechanism of expansive mudstone interbedded slope is studied. The specific research contents and results are as follows:. 1) on the basis of absorbing and drawing lessons from the research results of slope collapse at home and abroad, the classification and failure mode of collapse and the influencing factors of collapse are summarized. (2) the physical and mechanical properties of expansive mudstone are studied. A series of tests are carried out on the mudstone specimen, with emphasis on the relationship between the swelling force of mudstone and water content, and the relation between expansion rate and upper load, time and moisture content. By drawing the curve of the relationship between the influence factors and the expansion performance and regression analysis of the experimental data, the influence of each influencing factor on the mudstone performance is analyzed and the physical and mechanical parameters of the mudstone are obtained. (3) the characteristics of mudstone engineering analyzed by field exploration and laboratory tests, starting with the structural characteristics of slope body, starting with the development characteristics and rules of collapse, the conditions of formation of collapse, the typical collapse in the study section, etc. The collapse mechanism of expansive mudstone interbedded slope is put forward qualitatively. Using CDEM numerical simulation, the stress field, displacement field, plastic shear strain and element failure of slope under natural condition, rainstorm condition, earthquake condition are analyzed. In this paper, the collapse failure mechanism of slope under three conditions is studied. The evolution process of expansive mudstone interbedded slope collapse is reappeared and analyzed by discrete element method based on continuum mechanics under the consideration of structural plane and joint. Finally, comprehensive field investigation, laboratory tests and numerical simulation results show that the collapse mechanism of expansive mudstone interbedded slope can be summarized as follows: mudstone spalling. 鈫扴andstone fracture development. 鈫扴andstone partial fall. 鈫扖ollapse occurs.
【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U418.55

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