饱和尾矿砂地基上高填黄土路堤变形分析

发布时间：2018-05-07 09:10

本文选题：不均匀地基 + 尾矿砂　；参考：《长安大学》2015年硕士论文

【摘要】：尾矿砂地基由于特殊的形成原因,导致其在空间分布中具有不均匀变异性、高饱和性,在该种地基上修筑高填路堤会对路堤的安全和稳定性产生不可忽视的影响。鉴于此,本文依托山西王庄堡-繁峙高速公路项目,对现场CFG桩、水泥搅拌桩、碎石桩、碎石垫层等复合地基上的高填黄土路堤开展变形分析,进行了如下工作:(1)进行了CFG桩室内模型试验,获得了桩间土体的沉降数据和模型桩体在干湿两种状态下的弹性模量。(2)对有限元软件ADINA作了简要介绍,进行了CFG桩模型试验沉降的二维数值模拟,使模拟结果尽量与试验测试结果相同,获得了尾矿砂内摩擦角和粘聚力的数值。(3)利用ADINA对现场的CFG桩、水泥搅拌桩、碎石桩、碎石垫层等复合地基开展二维数值模拟,分析在地基不均匀程度、路堤填筑高度、桩长、桩间距影响下路堤土体的变形规律,并对四种处理方式下路堤地基土体最值的变化规律进行了对比。分析结果表明:随着地基在水平、垂直方向不均匀程度的增大,路堤右边坡至左侧尾矿砂层之间土体的水平位移增加明显,路堤竖向位移逐渐减小且其最大值逐渐向左偏移;随着路堤填筑高度的增加,路堤左右坡脚附近土体水平位移的增加越来越明显,并且竖向位移最大值的影响范围逐渐向上扩展,左移;随着桩长的增大,左边坡坡顶附近及右边坡土体的水平位移减小明显,竖向位移逐渐减小;随着桩间距的增大,路堤右边坡及其至地基左侧尾矿砂层之间土体的水平位移稍微增大。
[Abstract]:Due to the special formation of tailings sand foundation, it has inhomogeneous variability and high saturation in spatial distribution. The construction of high fill embankment on this kind of foundation will have an unnegligible effect on the safety and stability of embankment. In view of this, based on the Wangzhuang Bao-Fanchi Expressway Project in Shanxi, the deformation analysis of high fill loess embankment on site CFG pile, cement mixing pile, gravel pile, gravel cushion and other composite foundation is carried out. The results are as follows: (1) the indoor model test of CFG pile is carried out. The settlement data of soil between piles and the elastic modulus of the model pile under dry and wet conditions are obtained. The finite element software ADINA is introduced briefly. Two-dimensional numerical simulation of the settlement of CFG pile model test is carried out. The simulated results are as same as the test results, and the values of internal friction angle and cohesive force of tailings are obtained. The ADINA is used to make use of CFG pile, cement mixing pile and gravel pile in the field. Two-dimensional numerical simulation was carried out on the composite foundation, such as gravel cushion, to analyze the deformation law of embankment soil under the influence of uneven foundation, embankment filling height, pile length and pile spacing. The variation law of the maximum value of embankment soil under four treatment methods is compared. The results show that with the increase of horizontal and vertical uneven degree of foundation, the horizontal displacement of soil between the right slope of the embankment and the left tail-sand layer increases obviously, the vertical displacement of the embankment decreases gradually and its maximum value gradually shifts to the left. With the increase of embankment filling height, the horizontal displacement of soil near the left and right of the embankment becomes more and more obvious, and the influence range of the maximum vertical displacement gradually extends upward, and moves to the left with the increase of pile length. The horizontal displacement of the soil near the top of the left slope and the right side of the slope decreases obviously, and the vertical displacement decreases gradually, and with the increase of the pile spacing, the horizontal displacement of the soil between the right slope of the embankment and the left tailings of the foundation increases slightly.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U416.12

【相似文献】