具有衬砌圆形隧洞的弹塑性解  

ELASTIC-PLASTIC SOLUTION OF CIRCULAR TUNNEL WITH LINER

作　　者：任青文[1] 邱颖[1] 

机构地区：[1]河海大学工程力学系,南京210098

出　　处：《工程力学》2005年第2期212-217,共6页Engineering Mechanics

基　　金：教育部科学技术研究重点项目(02123)资助

摘　　要：圆形隧洞是土木工程中常见的结构。但是,以往分析无限大均匀介质中轴对称圆形隧洞应力变形和屈服区的公式,是在Mohr-Coulomb 屈服条件中的第一主应力为径向应力的情况下导出的,这样做还不够全面。根据不同的工况和不同的地应力条件,正确选择Mohr-Coulomb 屈服条件中的第一主应力,导出衬砌和围岩的屈服范围和应力计算公式,提出第一和第二临界压力的概念,并根据临界压力给出屈服区和应力计算公式的适用范围。最后用算例比较了该方法和以往传统方法的不同。The circular tunnel is a common structure in civil engineering. Engineers are always concerned about the stress field and displacement field of the liner and its surrounding rock. But the formulas of stresses, displacements and plastic range of the axisymmetric circular tunnel in the infinite uniform medium have been derived under the assumption that the first principal stress in Mohr-Coulomb yield function is always the normal uniform force acting on the inner face of the tunnel. The assumption is inadequate. In this paper, the formulas calculating yield range and stresses are deduced based on the proper choice of the first principal stress used in Mohr-Coulomb yield condition according to loads and in situ stresses. The concept of first and second critical pressure is introduced, which relate to the diameter of the circle tunnel, thickness of the liner, the elastic parameters and shear strength of the liner and its surrounding rock. The of applicability formulas is gained based on the critical pressures. An example is analyzed, and the yield range versus the inner pressure and stress distribution are presented. Results are compared to those based on the traditional method and significant disparity is observed. The greater of inner pressure, the greater of the difference.

关 键 词：圆形隧洞 衬砌 弹塑性解 Mohr-Coulomb屈服条件 临界压力 

分 类 号：U45[建筑科学—桥梁与隧道工程]