【作者】 魏文凯；

【导师】 罗书学；

【作者基本信息】 西南交通大学 ， 岩土工程， 2013， 硕士

【摘要】 随着我国经济建设的快速发展,特别是西部大开发战略的实施,西南山区高速铁路建设发展迅速。然而,在西南山区修建高速铁路时,由于地形地质条件的制约和工程建设的需要,在铁路沿线形成大量的路堤边坡及高挖方的路堑边坡。顺层岩质边坡是铁路沿线分布的主要边坡类型之一,降雨诱发的顺层滑坡时有发生,对高速铁路的建设和安全运营构成了巨大的威胁。因而,研究降雨入渗作用下顺层岩质边坡稳定性问题具有重大的现实意义。本文以贵广铁路K307工点为依托,采用相似模型试验和数值模拟手段,较为深入的研究了雨水入渗作用下顺层岩质边坡力学行为的变化规律。论文取得的主要成果如下：1.对岩质边坡渗流特性进行了分析,探讨了降雨入渗对岩质边坡的作用以及降雨入渗过程,给出降雨作用下含裂隙顺层岩质边坡稳定系数的实用算法,并应用该算法分析具体工程实例。2.依据相似理论,结合贵广铁路K307原型工点实际,开展了降雨入渗作用下顺层岩质边坡稳定性模型试验研究。拟定了边坡模型与原型的相似比,确定了强风化岩、弱风化岩和软弱夹层相似材料的配合比；根据相似比确定了支挡结构材料；设计了模型试验,确定了传感器的布置方案,建立了边坡试验模型。3.开展了边坡倾角分别为25°和30°的自然边坡、锚杆框架梁支挡边坡以及锚杆框架梁加抗滑桩支挡边坡的降雨模型试验,研究了降雨入渗作用下坡体软弱夹层含水量、孔隙水压力、坡体位移以及支挡结构内力变化规律,并将不用倾角的边坡在降雨作用下力学特性进行对比分析,结果表明坡体下部位移最大,边坡倾角增大非常不利于边坡稳定,支挡结构对边坡稳定作用明显,不同形式的支挡结构对边坡稳定所起的作用有所差异。4.基于有限元基本理论,结合建立的边坡模型,采用Midas/GTS岩土数值分析软件分析了不同降雨强度条件下坡体内孔隙水压力分布,分析了降雨入渗过程中的流—固耦合现象,进而分析了降雨入渗作用下边坡稳定性和边坡位移,以及支挡结构内力变化规律,并将数值分析结果与试验结果进行了对比,分析表明两种研究方法得到的总体变化趋势是基本一致的。更多还原

【Abstract】 As rapid development of China’s economy and implementation of the large-scale development strategy for the western region, high speed railway construction develops very rapidly in southwest China. However, a large quantity of embankment slopes and cutting slopes have boomed along railway due to complicated terrain and geological conditions and the necessary of construction during construction of high speed railway in southwest China. The bedded rock slope is one of the familiar types of slopes along railway. The frequent occurrence of bedding landslide induced by rainfall is a big hazard to the construction and operation of high speed railway. Thus it has significant practical meaning to carry on the research on the stability of bedded rock slope due to rainfall infiltration. Based on K307work site, this paper conducts systematical research work on the mechanical behaviors of rock bedded slope under rainfall by the research method of the similar simulation test and the numerical simulation analysis. The main research achievements are as follows:1. The characteristic of seepage flow for rock slope is analyzed, and the effect of rainfall infiltration on rock slope is studied. This paper also carries on research on the process of rainfall infiltration. The method to calculate stability coefficient of fractured rock slope is given and being used in analyzing project case.2. According to the similarity theory, combined with project fact of K307work, similarity model test study on the stability of bedded rock slope due to rainfall infiltration have been carried out. The similarity ratio has been constructed and the mix ratio of simulation materials for intensely weathered rock, slightly weathered rock and soft interlayer The material for retaining structure also has been constructed on the basis of similarity ratio. This paper designs model test and decides the layout plan for sensors. The test model has been constructed finally.3. This paper carries on model tests of natural slope, slope retained by anchor frame beam and slope retained by anchor frame beam and anti-slide pile with slope angle of25°and30°under the condition of rainfall. The change rule of liquid water content, pore water pressure and slope displacement in soft interlayer as internal force of retaining structure during rainfall has been studied and comparative analysis of slope mechanical behaviors with different angles has been done. The achievements shows that the biggest displacement appears at the lower part of slope, the increase of slope angle turns against stability of slope, retaining structure plays an important role in slope stability, and different kinds of retaining structure plays different roles. 4. Based on the finite element theory and combined with the established slope model, Midas/GTS has been used to analyze distribution of slope pore water pressure under different rainfall intensity and change rule of internal force for retaining structure. Furthermore, the stability and displacement of slope during rainfall has been studied. This paper also carries research on internal force of retaining structure during rainfall. The results of numerical analysis were compared with real data obtained from laboratory tests, the results show that changing trends obtained with both methods are basically consistent.更多还原