环形超深基坑围护结构受力变形特性分析  

Mechanical and deformation characteristics of enclosure structure for annular extra-deep excavation

作　　者：罗耀武[1,2] 凌道盛[1] 陈云敏[1] 胡琦[3] 陈峥[4] 

机构地区：[1]浙江大学软弱土与环境土工教育部重点实验室,杭州310027 [2]黄河勘测规划设计有限公司,郑州450003 [3]浙江工业大学,杭州310014 [4]华东电力设计院,上海200063

出　　处：《岩土力学》2011年第2期617-622,共6页Rock and Soil Mechanics

摘　　要：结合上海世博500kV变电站超深基坑实际工程,采用平面应变及轴对称弹性地基有限元分析模型对基坑围护结构的空间效应进行简化,分析了环形基坑空间效应、内衬墙以及水土压力模式对围护结构受力变形特性的影响,并与实测结果进行比较。结果表明,环形基坑围护结构的空间效应对其受力变形特性影响很大,在计算过程中必须考虑围护结构环向刚度对径向刚度的贡献;内衬墙作用类似于环形支撑,对地下连续墙受力及变形是有利的;地下连续墙水平位移实测值最接近于侧压力系数1.0的轴对称有限元分析结果;地下连续墙环向应力和弯矩实测值位于按规范水土分算与侧压力系数1.0的轴对称有限元计算结果之间。Based on the deep excavation of Shanghai 2010 Exposition 500 kV substation,the plane strain and axisymmetric elastic foundation FEM are used to simplify the space effect of the enclosure structure.The space effect of the annular enclosure structure,the inner liner and the different water and soil pressure distribution model are considered for the mechanical and deformation characteristics of enclosure structure.Through comparision between the calculated and measured results,several results are obtained： the space effect of the annular enclosure structure has a great influence on the mechanical and deformation characteristics of it;the ring stiffness of the enclosure structure must be considered during calculation;the inner liner is beneficial to the mechanical and deformation of the diaphragm wall,like a ring supporting;the measured horizontal displacement of the diaphragm wall is close to the result of axisymmetric finite element analysis when lateral pressure coefficient is 1.0;the measured hoop stress and bending moment of diaphragm wall are between the result of estimating water and earth pressure separately and lateral pressure coefficient is 1.0.

关 键 词：环形超深基坑 围护结构 

分 类 号：TU753[建筑科学—建筑技术科学]