北京地区土钉作用机理及土钉墙工作特性的试验研究
发布时间：2018-08-23 14:50
【摘要】：本文以粉质粘土和粉质砂土中的深基坑土钉支护为研究对象，通过自主设计的物理模型试验系统，对土钉作用机理及土钉墙的工作特性进行研究。首先介绍了试验所需的物理模型、测试系统及试验实施过程；然后详细分析了土压力、土钉轴力、墙顶水平位移在各步开挖及加载状况下的分布变化规律；并且在物理模型试验的基础上进行了FLAC3D模拟研究，最后结合具体工程进行了土钉支护的应用研究。通过一系列研究发现（1）开挖中墙内各测点侧向土压力先增大后减小再逐渐增加，而坑底土压力则一直增大；（2）就某一层土钉而言，其下部紧临土层开挖对其轴力影响最大，且墙体水平位移较大处附近的土钉轴力也较大；（3）土体开挖是墙体产生位移的主要原因，随开挖的进行，墙体位移不断增加，，且在墙顶施加一定均布荷载时，墙顶水平位移随荷载的增大近似线性增长；（4）当土质为粉质砂土时，土钉墙的水平位移的最大值应控制在基坑开挖深度的4‰以下，当大于4‰后，应立刻采取其他辅助措施以保证墙体稳定。
[Abstract]:In this paper, the soil nailing support of deep foundation pit in silty clay and silty sandy soil is taken as the research object, and the mechanism of soil nailing and the working characteristics of soil nailing wall are studied through the self-designed physical model test system. Distribution and variation of nail axial force and horizontal displacement of the top of the wall under different excavation and loading conditions were studied by FLAC3D simulation on the basis of physical model test. Finally, the application of soil nailing support was studied in combination with specific projects. The soil pressure at the bottom of the pit increases gradually when the soil nail is small and then small; (2) For a certain layer of soil nail, the excavation at the bottom of the soil nail has the greatest influence on its axial force, and the axial force of soil nail near the large horizontal displacement of the wall is also large; (3) soil excavation is the main reason for the displacement of the wall, with the excavation, the displacement of the wall increases continuously, and the displacement of the wall increases. When a certain uniform load is applied on the top of the wall, the horizontal displacement of the top increases approximately linearly with the increase of the load; (4) When the soil is silty sand, the maximum horizontal displacement of the soil nailing wall should be controlled below 4 of the excavation depth of the foundation pit, and when it is greater than 4, other auxiliary measures should be taken immediately to ensure the stability of the wall.
【学位授予单位】：中国矿业大学（北京）
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TU476
本文编号：2199399
[Abstract]:In this paper, the soil nailing support of deep foundation pit in silty clay and silty sandy soil is taken as the research object, and the mechanism of soil nailing and the working characteristics of soil nailing wall are studied through the self-designed physical model test system. Distribution and variation of nail axial force and horizontal displacement of the top of the wall under different excavation and loading conditions were studied by FLAC3D simulation on the basis of physical model test. Finally, the application of soil nailing support was studied in combination with specific projects. The soil pressure at the bottom of the pit increases gradually when the soil nail is small and then small; (2) For a certain layer of soil nail, the excavation at the bottom of the soil nail has the greatest influence on its axial force, and the axial force of soil nail near the large horizontal displacement of the wall is also large; (3) soil excavation is the main reason for the displacement of the wall, with the excavation, the displacement of the wall increases continuously, and the displacement of the wall increases. When a certain uniform load is applied on the top of the wall, the horizontal displacement of the top increases approximately linearly with the increase of the load; (4) When the soil is silty sand, the maximum horizontal displacement of the soil nailing wall should be controlled below 4 of the excavation depth of the foundation pit, and when it is greater than 4, other auxiliary measures should be taken immediately to ensure the stability of the wall.
【学位授予单位】：中国矿业大学（北京）
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TU476
【参考文献】
相关期刊论文 前10条
1 何夕平;土钉墙基坑支护原理及其在合肥地区应用情况分析[J];安徽建筑;2003年04期
2 钟昌云,方玉树;土钉墙技术及其发展前景[J];重庆工业高等专科学校学报;2004年01期
3 王建党,贾立宏,秦四清,李造鼎;深基坑土钉支护抗拔机理[J];东北大学学报;1999年01期
4 吴琦琪;;复合型土钉支护结构有限元数值分析[J];低温建筑技术;2006年03期
5 徐少曼,李树华,陈孝贤;软土深基坑开挖的模型试验研究[J];福建建筑;2000年S2期
6 陈昌禄,冯铜新;护壁工程土钉支护模型试验研究[J];工程建设与设计;2005年11期
7 宋二祥，陈肇元;土钉支护及其有限元分析[J];工程勘察;1996年02期
8 杨强;;土钉基坑支护有限元分析与信息化监测施工技术在工程中的应用[J];国外建材科技;2007年03期
9 张明聚,陈肇元,宋二祥;深基坑土钉支护有限元分析方法及应用[J];工业建筑;1999年09期
10 马宁;;对深基坑土钉支护机理与控制技术研究的论述[J];广东科技;2007年05期
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