深基坑复合土钉支护的三维有限元数值分析  

3D numerical analysis on composite soil nailed structure for deep excavation with FEM

作　　者：李彦初[1,2] 陈轮[1] 

机构地区：[1]清华大学水沙科学与水利水电工程国家重点试验室,北京100084 [2]同济大学地下建筑与工程系,上海200092

出　　处：《工程勘察》2012年第2期11-15,32,共6页Geotechnical Investigation & Surveying

基　　金：水沙科学与水利水电工程国家重点实验室基金项目(2009-ZY-3)

摘　　要：复合土钉支护作为一种新型支护技术具有广阔的应用前景,但目前相关的研究远远落后于工程实践。本文运用有限元软件ABAQUS建立了超前钢管桩、土钉、预应力锚索三种支护结构不同组合的复合土钉支护和简单土钉支护的三维模型,对基坑的开挖支护过程进行了数值模拟。研究表明:复合支护下基坑开挖面最大水平位移发生在基坑下部;钢管桩对开挖面中上部水平位移限制作用明显;土钉轴力的分布成中间大、两端小的形式。本文的结果与前人的研究成果相符,可以为工程提供一定参考。The composite soil nailed structure is a kind of new supporting technique which is provided with the broad prospect. For the sake of disclosing the behavior of the composite soil nailed structure and improving the current design method, the 3D models for the simple soil nailed structure and the composite soil nailed structure with the different combinations of the leading piles, nails, pre-stressed anchor rods are developed by using the commercial code ABAQUS, and the numerical analysis with FEM is carried on the process of the excavating and supporting of the foundation pit. The distribution of the axial forces of soil nails and the lateral displacement of excavation face are studied. The results of the numerical simulation show that the maximum lateral displacement of excavation face is at the bottom section of the excavation face, and the restriction of leading piles on the lateral displacement of the upper excavation face is obvious, but is not distinct on the lateral displacement of the lower excavation face. The axial forces at the middle parts of soil nails are bigger than that at the ends of the soil nails. The results reflect that leading piles and pre-stressed anchor rods can decrease the axial forces of soil nails effectively. To some degree, these results have the reference value to engineering practice.

关 键 词：基坑支护 复合土钉 超前桩 土钉轴力 有限元 

分 类 号：TU476[建筑科学—结构工程]