Upper bound solutions for supporting pressures of shallow tunnels with nonlinear failure criterion

作     者：YANG Xiao-li ZHANG Dao-bing WANG Zuo-wei 

作者机构：School of Civil Engineering Central South University Changsha 410075 China 

出 版 物：《Journal of Central South University》 (中南大学学报（英文版）)

年 卷 期：2013年第20卷第7期

页      面：2034-2040页

核心收录：

学科分类：08[工学] 080104[工学-工程力学] 0815[工学-水利工程] 0801[工学-力学（可授工学、理学学位）] 

基　　金：Foundation item: Project(2013CB036004) supported by the National Basic Research Program of China Project(51178468) supported by the National Natural Science Foundation of China 

主　　题：shallow tunnel nonlinear criterion limit analysis supporting pressure failure mechanism 

摘      要：Linear failure criterion is widely used in calculation of earth pressure acting on shallow tunnels. However, experimental evidence shows that nonlinear failure criterion is able to represent fairly well the failure of almost all types of rocks, A nonlinear Hock-Brown failure criterion is employed to estimate the supporting pressures of shallow tunnels in limit analysis framework. Two failure mechanisms are proposed for calculating the work rate of extemal force and the internal energy dissipation. A tangential line to the nonlinear failure criterion is used to formulate the supporting pressure problem as a nonlinear programming problem. The objective function formulated in this way is minimized with respect to the failure mechanism and the location of tangency point. In order to assess the validity, the supporting pressures for the proposed failure mechanisms are calculated and compared with each other, and the present results are compared with previously published solutions when the nonlinear criterion is reduced to linear criterion. The agreement supports the validity of the proposed failure mechanisms. An experiment is conducted to investigate the influences of the nonlinear criterion on collapse shape and supporting pressures of shallow tunnels.