平移模式下刚性挡土墙三维被动滑裂面形态的试验与数值模拟

发布时间：2018-03-01 09:09

本文关键词： 刚性挡土墙三维滑裂面平移模式空间形态模型试验数值模拟　出处：《合肥工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：挡土墙后滑裂面的空间效应是客观存在的,研究滑裂面的空间形态对于理论分析三维土压力具有基础性意义。采用自主设计的模型试验装置,重复开展6次试验,通过监测脆性玻璃条的断裂位置获取了确切的滑裂面的空间形态,并且分析了滑裂面在主平面的投影形态和土体隆起形态。用数值模拟的方法计算了100个工况,分析了滑裂面空间形态和主平面的投影形态与挡土墙宽深比、土体内摩擦角及墙土接触面粗糙程度之间的关系。通过研究,主要获得了以下研究成果:(1)用试验和数值模拟的方法获得了三维被动滑裂面形态:滑裂面横剖面宽度大于挡土墙宽度,随着距挡土墙距离的增加,横剖面底部的水平段宽度逐渐减小,横剖面最低部的高度逐渐增加,横剖面形态由“U”型逐渐变为“V”型;滑裂面纵剖面后半部分近似为直线,各纵剖面形态之间存在差异。(2)获得了滑裂面在主平面上的投影形态。从挡土墙后先以斜线往外侧扩展,斜线与挡土墙垂线夹角近似为扩展角,距挡土墙最远处为与挡土墙平行但宽度小于挡土墙宽度的直线段,斜线与直线段之间近似以圆弧段连接。主平面投影形态关于挡土墙中垂线对称。(3)对滑裂面空间形态的影响因素进行分析总结。(1)随着挡土墙宽深比增大:滑裂面的空间特性逐渐不明显;滑裂面纵剖面破裂角减小。(2)随着土体内摩擦角的增加:滑裂面纵剖面直线段的破裂角逐渐减小;横剖面最低位置的高度逐渐减小,横剖面宽度范围逐渐增大,横剖面由底部往顶部过渡的趋势由比较陡逐渐变得平缓;主平面投影形态的宽度及距挡土墙最远距离均出现线性增加。(3)墙土接触面的粗糙程度对于滑裂面的形态和主平面投影形态影响较小。(4)土体达到被动极限破坏的位移量。平移模式下有限宽深比的刚性挡土墙后无黏性土体达到被动极限破坏所需达到位移量为(10%~12%)H。
[Abstract]:The spatial effect of the sliding surface behind the retaining wall is objective. The study of the spatial form of the sliding surface is of fundamental significance to the theoretical analysis of three-dimensional earth pressure. By monitoring the fracture position of brittle glass strip, the exact spatial shape of the slip surface is obtained, and the projection shape and the soil uplift shape of the slip surface in the main plane are analyzed. The 100 working conditions are calculated by numerical simulation. This paper analyzes the relationship between the spatial shape of sliding crack surface and the projection form of main plane and the ratio of width to depth of retaining wall, the angle of internal friction of soil and the roughness of the interface between wall and soil. The following research results are obtained: (1) Three-dimensional passive sliding surface is obtained by experiment and numerical simulation: the width of the transverse section of the sliding surface is larger than the width of the retaining wall, and with the increase of the distance from the retaining wall, The width of the horizontal section at the bottom of the cross section gradually decreases, the height of the lowest part of the section increases gradually, the shape of the cross section changes from "U" to "V", the latter half of the longitudinal section of the slip surface is approximately straight line, The projection form of the slip surface on the main plane is obtained. The angle between the inclined line and the vertical line of the retaining wall is similar to that of the vertical line from the retaining wall to the outside, and the angle between the diagonal and the vertical line of the retaining wall is similar to that of the vertical line of the retaining wall. The furthest distance from the retaining wall is a straight section parallel to the retaining wall but having a width less than the width of the retaining wall, The main plane projection shape about vertical line symmetry in retaining wall. Analysis of the factors affecting the spatial form of sliding crack surface. Conclusion. 1) with the increase of the width to depth ratio of retaining wall: the sliding crack surface. The spatial characteristic is not obvious gradually; With the increase of internal friction angle of soil, the fracture angle of straight section of longitudinal section of slip fracture surface decreases gradually, the height of the lowest position of cross section decreases gradually, and the width range of cross section increases gradually. The trend of the transition from bottom to top of the cross section gradually changed from steepness to smoothness. The width of the main plane projection form and the farthest distance from the retaining wall are linearly increased.) the roughness degree of the interface between the wall and the soil has less influence on the shape of the sliding surface and the projection form of the main plane. 4) the soil reaches the passive limit failure position. Displacement. The displacement required for the passive limit failure of the non-viscous soil behind a rigid retaining wall with a finite aspect ratio in the translational mode is 10 ~ (10) and 12 ~ (12) H ~ (-1).
【学位授予单位】：合肥工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU476.4

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