摘要
以南京某地铁车站深基坑工程为研究对象,介绍该工程场区的地质条件,支护形式及施工工序;分析该基坑在开挖过程中围护结构的位移、支撑轴力及基坑周围土体地表沉降的变化,通过有限元软件Plaxis对基坑开挖进行数值模拟,并将计算结果与实测结果进行比较分析,二者结果基本吻合,并且通过进一步研究得到了支护结构抗弯刚度EI、坑边超载及开挖对基坑变形规律的影响结果。增加支护结构的抗弯刚度能一定程度减小地连墙的水平位移,随着坑边超载P的不断增大墙顶水平位移不断加大,当P=50 k Pa时,围护结构墙顶范围内发生明显屈服。而随着开挖深度的不断增大,超载对地连墙水平位移的影响系数不断减小。基坑开挖时。地下连续墙最大侧移位置大致位于开挖面附近,且随着开挖深度的增大而逐渐下移。当土体开挖至坑底且未施工底板和垫层时,此时基坑处于最危险状态。
In deep foundation pit engineering of nanjing subway station as the research object, introduces the engineering geological conditions in jobsite, the support form and construction process; Analysis of the foundation pit displacement of retaining structure in the process of excavation and supporting axial force and the change of the surface settlement of soil around the foundation pit, the pit excavation are numerically simulated by finite element software Plaxis, analysis and comparing the calculated results with measured results, the two results are basically consistent, and the supporting structure is obtained by further research on bending stiffness EI, pit overload and the result of the influence of excavation of foundation pit deformation law. Can increase the flexural stiffness of supporting structure to a certain extent reduce the horizontal displacement of wall, with the increase of test pit overload P wall top horizontal displacement increasing, when P = 50 kPa, retaining wall structure within the scope of apparent yield. As the increasing of excavation depth, the overload of the wall and decreases the influence of the horizontal displacement coefficient. In the excavation of foundation pit. Underground continuous wall maximum lateral position near the excavation surface, and down gradually along with the increase of excavation depth. When the soil excavation to the bottom slab and cushion layer, and construction at the moment of foundation pit in the most dangerous state.
出处
《华东交通大学学报》
2015年第1期65-70,共6页
Journal of East China Jiaotong University
关键词
有限元
地连墙
抗弯刚度
数值分析
finite element
ground wall
bending stiffness
numerical analysis
