不同洞型条件下填土性质对涵顶土压力及土拱效应的影响研究

发布时间：2018-03-23 03:37

本文选题：涵洞　切入点：填土性质　出处：《太原理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着我国经济的高速发展，涉及民生的基本建设也在蓬勃发展。而涵洞作为最常见的一种工程建筑，广泛应用于水利、公路、铁路、土木、市政等工程领域。本文通过ANSYS有限元分析软件，，就箱涵和半圆拱涵在不同性质填土条件下的土压力进行正交试验研究，找出最敏感的填土性质指标，在此基础上对覆土中小主应力偏转轨迹线进行简要分析。主要结论如下：（1）砂性土填埋下的箱型涵洞，填土内摩擦角对土压力的影响最大，随着内摩擦角的增大，土压力系数先快速增大，后趋于平稳。（2）粘性土填埋下的箱型涵洞，填土泊松比对土压力的影响最大，土压力系数随着泊松比的增大呈现下降趋势，且在全区间内，下降速率基本相同。（3）砂性土填埋的半圆拱涵，填土内摩擦角对土压力的影响最大，土压力系数随着内摩擦角的增大而增大，其增长速率越来越慢。（4）粘性土填埋的半圆拱涵,填土泊松比对土压力系数的影响最大，土压力系数随着泊松比的增大出现下降趋势，且在泊松比μ0.37的区间，下降速率相对较大。（5）填土为砂性土的情况下，填土内摩擦角为其最敏感因素。箱涵顶部填土的小主应力轨迹线偏转程度随着内摩擦角的增大而增大；半圆拱涵顶部填土的小主应力的偏转程度几乎不随填土内摩擦角的变化而变化。（6）填土为粘性土的情况下，填土泊松比为最敏感因素。箱涵顶部填土的小主应力的偏转程度随着泊松比的增大而增大。半圆拱涵顶部填土的小主应力的偏转随着泊松比的增大而有所增大。在各工况下，小主应力轨迹线的偏转程度都随着距涵顶高度的增大而减小。等沉面以上小主应力轨迹线水平。
[Abstract]:With the rapid development of China's economy, the capital construction involving people's livelihood is booming. As the most common engineering building, culvert is widely used in water conservancy, highway, railway, civil engineering, municipal engineering and other fields. In this paper, the earth pressure of box culvert and semi-circular arch culvert under different filling conditions is studied by means of ANSYS finite element analysis software, and the most sensitive index of filling property is found out. On this basis, a brief analysis of the trajectory of the small and medium principal stress deflection in overlying soil is carried out. The main conclusions are as follows:. 1) for box culverts filled with sandy soil, the internal friction angle of the fill has the greatest influence on the earth pressure. With the increase of the internal friction angle, the coefficient of soil pressure increases rapidly and then tends to steady. (2) in the box culvert filled with cohesive soil, the Poisson ratio has the greatest influence on the earth pressure, and the coefficient of soil pressure decreases with the increase of Poisson's ratio, and the decreasing rate is basically the same in the whole region. (3) in the semi-circular arch culvert filled with sandy soil, the internal friction angle of the fill has the greatest influence on the earth pressure, and the coefficient of the earth pressure increases with the increase of the internal friction angle, and the growth rate of the soil pressure coefficient increases more and more slowly. (4) in the semi-circular arch culvert filled with clayey soil, Poisson's ratio has the greatest influence on the coefficient of soil pressure, and the coefficient of soil pressure decreases with the increase of Poisson's ratio, and the decreasing rate is relatively large in the range of Poisson's ratio 渭 0.37. (5) when the fill is sandy, the internal friction angle of the fill is the most sensitive factor. The degree of small principal stress trajectory deflection increases with the increase of the internal friction angle at the top of the box culvert. The degree of deflection of minor principal stress at the top of the arch culvert is almost unchanged with the change of the angle of friction within the fill. If the fill is clay, Poisson's ratio of fill is the most sensitive factor. The degree of deflection of small principal stress of top fill of box culvert increases with the increase of Poisson's ratio. The deflection of small principal stress of top fill of semi-circular arch culvert increases with the increase of Poisson's ratio. The degree of deflection of the small principal stress locus decreases with the increase of the height from the culvert top.
【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】：TU432

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