板岩路堑边坡的开挖扰动效应与防护技术研究

【作者】 陈芬；

【导师】 傅鹤林；

【作者基本信息】 中南大学 ， 岩土工程， 2008， 硕士

【摘要】 高速公路边坡一直是国内外关注的研究热点,现有比较成熟的方法,但板岩路堑高陡边坡,研究的人较少,其工程中高陡的特性,使其在开挖施工过程中可能产生的危害性较大,同时,考虑到降雨对这类边坡稳定性和施工过程有较大的影响,对其不同含水率的板岩高陡边坡的稳定性、不同开挖阶段的扰动效应的分析研究,是一个极有价值的课题,能够为工程的设计、施工提供一定的参考和依据。本文以衡炎高速三合同段的高路堑板岩边坡为依托工程,对板岩边坡的开挖扰动效应、雨水对边坡开挖稳定性的影响及板岩路堑边坡的防护技术进行了研究,主要内容包括:(1)通过全风化板岩室内试验,得到全风化板岩的物理和力学参数,并通过制备不同含水率、焖料时间的试样进行土工试验,得到含水率、焖料时间因素对全风化板岩力学特性的影响规律。(2)应用极限平衡法和有限差分法计算衡炎三合同段板岩路堑边坡的稳定系数,评价其稳定性,并将两种计算方法得到的安全系数、滑动面形状、滑面位置进行比较,相互验证两种计算方法的可信度。(3)对天然含水率下的坡体的开挖扰动效应进行数值模拟分析,并将计算结果与现场监测结果进行比较分析,验证试验所得参数和数值模型的正确性。(4)结合室内试验所得板岩不同含水率下的物理和力学参数,模拟计算不同含水率下坡体的开挖扰动效应,得到在开挖状态下,含水率对坡体稳定性的影响规律。(5)针对板岩路堑边坡开挖扰动效应以及含水率对板岩边坡开挖扰动影响,结合地质、地形,选择不同的防护方案,并通过数值模拟对支护加固后效果进行分析。更多还原

【Abstract】 The research of highway slope has always been a focus at home and abroad, and there are riper methods now,but the high-steep cutting of slate slope, there are studied by less people.The characteristic of high and steep in its project, making more harmfulness that may produce in the course of excavating and constructing.Meanwhile,considering the rainfall has greater influence on slope stability and construction course, the perturbation effect analysis of slate high slope in different excavating stage and different moisture content is an extremely valuable subject.Relying on the project of the high-steep cutting slate slope in the third contract section of Hengyan highway, the influence of excavating stage and moisture content on the stablity of the slate slope,the protection technology of the high-steep cutting slate slope,which were studied in the paper,the main content contains:(1) The laboratory experiments of the complete weathering slate were carried on, obtained physics and mechanics parameter of the entire decency slate, and with the sample of different moisture content and different covered time,carried on the laboratory experiments,obtained the influence of moisture conten and covered time on the mechanics characteristic of complete weathering slate(2) The safety factor of the cutting slate slope in the third contract section of Hengyan highway is calculated, with the limiting equilibrium method and the finite difference method.Through compared the safety factor, the sliding surface shape, the sliding face position which obtained by the two methods,confirmed mutually the confidence level of the two methods.(3) With finite difference method , the exeavating disturbation effect of the slate slope with natural moisture content was analysed,and by comparing the computed result and the scene monitor result, the parameters which obtained in laboratory experiments and the accuracy of the numerical model were confirmed.(4) Combined the physics and mechanics parameter of the slate with different moisture content,which obtained in the laboratory experiments, and by analysed the exeavating disturbation effect of the slate slope with different moisture content, obtained the relation between slope stability and moisture content.(5) In view of the excavating disturation effect and the influence of moisture conten on the slope stability, combining the geology, the terrain, choosed different fence plan,and analysed the effect of the fence by the value simulation.更多还原