软土深基坑变形特征的数值模拟分析研究

选用Drucker-Prager弹塑性本构关系,建立了模拟深基坑开挖和支护全过程的平面有限元数值模型。运用该模型并结合工程实际,分析了深基坑开挖过程中边坡土体的应力场和塑性区的分布规律以及沉降、位移和坑底隆起3种基坑变形的机理,找出了影响深基坑变形的主要因素:支护结构的刚度、支护结构入土深度、基坑开挖深度和宽度以及地层强度参数等。

NUMERICAL SIMULATING ANALYTICAL STUDY ON DEFORMATION CHARACTERISTICS OF EXCAVATION ENGINEERING OF SOFT SOIL

This paper establishes one plane FEM numerical analysis model based on Drucker-Prager elastic-plastic constitutive relation to simulate excavating and supporting of foundation pit. By means of this model combining with actual engineering it analyses the distribution rule of stress field and plastic zone and the deformation mechanism of displacement, sedimentation and bottom heave during excavation and retaining and finds the main factors that affect the deformation, that is, stiffness coefficient and stiffness of fulcrum installing and depth of excavation and soil parameters.