盾构隧道衬砌结构应力与变形的三维数值模拟与模型试验研究

结合广州地铁三号线盾构隧道工程实例,提出钢筋混凝土衬砌结构三维非线性有限元计算模型,应用非线性有限元程序ANSYS分析了上部和周围土体荷载作用下衬砌的应力场与变形情况。结构计算模型采用三维实体单元,考虑了衬砌与周围土体的共同作用、土体和钢筋混凝土材料的非线性性质,通过模型刚度折减考虑了管片接头的不连续性对衬砌应力和变形性质的影响。为验证数值分析结果,进行了衬砌结构的相似模型试验。给出了衬砌结构的应力场、应变场、结构整体位移以及裂纹的分布图。

3D NUMERICAL SIMULATION OF STRESS AND STRAIN PROPERTIES OF CONCRETE SHIELD TUNNEL LINING AND MODELING EXPERIMENTS

In this paper, a three-dimensional nonlinear FEM model of RC shield tunneling lining is proposed to deal with the simulation of Guangzhou Underground Line 3. The nonlinear FEM code ANSYS is used to analyze the stress and strain behavior of lining structure which is subjected to the covered soil and the applied surface loads. Three-dimensional solid elements are adopted in this numerical model. The interaction of lining and around soil, the nonlinear properties of concrete and soil is considered. The influence of the segment joints on the stress, strain and crack properties of lining is discussed allowing for the reduction of joint rigidity. A series of physical model tests were designed to verify the numerical solutions to the lining structure. The stress, strain, structural displacements and crack distribution are illustrated in this paper.