考虑土拱效应的挡土墙非极限状态被动土压力研究

发布时间：2018-02-21 10:33

本文关键词： 被动土压力土拱效应平移模式位移场土压力系数　出处：《太原理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：1978年改革开放之后，尤其是20世纪中后期，我国的现代化经济飞速发展，伴随着这种快速发展，工程领域中的基础设施以及一些大型的重点工程项目也在热风热浪的进行着。其范围涉及市政工程、建筑工程、机电工程、公路工程、桥梁工程、铁路工程以及水利工程等多个领域。其中以公路、水利以及铁路取得的成就最为令人为瞩目。这三大基础工程领域往往需要穿山越岭，这就使得挡土墙越来越多的出现在工程建设中。本文以水平位移下的刚性挡土墙作为研究对象，通过有限元软件ANSYS数值解析挡土墙后土体被动非极限状态下的相对位移区，以及相对位移区中的土拱效应，并且研究土拱形状、性质，结合水平微分单元分析法研究非极限状态下被动土压力的大小、分布等。本文的研究工作如下：（1）挡土墙向土体方向发生一定水平位移，土体处于非极限状态时，墙后回填土体存在相对位移区，该区形状为倒梯形。相对位移区范围大小受到墙体位移、回填土体内摩擦角及回填土体弹性模量等因素的影响。墙体位移增大，，相对位移区范围增大；回填土体内摩擦角增大，相对位移区范围减小；回填土体弹性模量增大，相对位移区范围增大。（2）挡土墙后非极限状态被动土压力受到墙体位移、回填土体内摩擦角及回填土体弹性模量等影响。随着墙体位移和回填土体内摩擦角的增大，被动土压力增大，总土压力力增大，合力作用点降低。（3）就刚性挡土墙以平移模式挤压土体情况下，数值研究被动非极限状态大主应力轨迹线——大主应力拱拱曲线是一条以e为底的指数曲线。大主应力土拱曲线受到墙体位移及墙后填土中内摩擦角的影响。墙体位移增大，土拱曲线曲率增大，曲线越弯曲；填土内摩擦角增大，土拱曲线曲率减小，曲线越平缓。（4）利用被动非极限状态下的土拱曲线，分析得到挡土墙非极限状态的被动土压力系数。结合水平层分析法，建立挡土墙非极限状态下被动土压力分布、合力大小及其作用点的计算理论。
[Abstract]:After the reform and opening up in 1978, especially in the middle and late period of 20th century, the modern economy of our country developed rapidly, which was accompanied by this rapid development. Infrastructure in the field of engineering and a number of large key engineering projects are also under way in hot wind and heat waves. Their scope covers municipal engineering, building engineering, mechanical and electrical engineering, highway engineering, bridge engineering, Railway engineering and water engineering, among them, highway, water and railway achievements are most remarkable. These three basic engineering areas often need to cross mountains and mountains. This makes the retaining wall more and more appear in the engineering construction. In this paper, the rigid retaining wall under horizontal displacement is taken as the research object, and the relative displacement region of the soil in the passive non-limit state and the soil arch effect in the relative displacement zone are analyzed by the finite element software ANSYS. And the shape and properties of soil arch are studied, and the size and distribution of passive earth pressure in non-limit state are studied by using horizontal differential unit analysis. The research work in this paper is as follows:. 1) the retaining wall has a certain horizontal displacement to the soil. When the soil is in the non-limit state, there is a relative displacement area in the backfill soil, and the shape of the backfill soil is inverted trapezoid, and the relative displacement range is affected by the wall displacement. The wall displacement increases, the relative displacement range increases, the friction angle increases, the relative displacement region decreases, and the elastic modulus of backfill soil increases. The range of relative displacement region increases. 2) the passive earth pressure behind the retaining wall is affected by the wall displacement, the friction angle of the backfill and the elastic modulus of the backfill soil. With the increase of the displacement of the wall and the friction angle of the backfill, the passive earth pressure increases. The total earth pressure increases and the joint action point decreases. (3) in the case of the rigid retaining wall squeezing the soil in a translational mode, Numerical study on the trajectory of large principal stress in passive non-limit state the curve of large principal stress arch arch is an exponential curve based on e. The large principal stress soil arch curve is affected by the wall displacement and the internal friction angle in the backfill of the wall, and the wall displacement increases. The curvature of soil arch curve increases, the curve is more curved, and the curvature of soil arch curve decreases with the increase of friction angle of filling soil, and the curve is more gentle. 4) the passive earth pressure coefficient of the retaining wall in the non-limit state is obtained by using the soil arch curve in the passive non-limit state, and the distribution of the passive earth pressure in the non-limit state of the retaining wall is established by combining the horizontal layer analysis method. The calculation theory of force and its point of application.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU476.4;TU432

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