Upper bound limit analysis of roof collapse in shallow tunnels with arbitrary cross sections under condition of seepage force  

作　　者：杨小礼 覃长兵 

机构地区：[1]School of Civil Engineering Central South University

出　　处：《Journal of Central South University》2014年第11期4338-4343,共6页中南大学学报（英文版）

基　　金：Project(2013CB036004)supported by the National Basic Research Program of China;Projects(51178468,51378510)supported by National Natural Science Foundation of China

摘　　要：The analytical solutions for predicting the exact shape of collapse mechanisms in shallow tunnels with arbitrary excavation profiles were obtained by virtue of the upper bound theorem of limit analysis and variation principle according to Hoek-Brown failure criterion. The seepage force was included in the upper bound limit analysis, and it was computed from the gradient of excess pore pressure distribution. The seepage was regarded as a work rate of external force. The numerical results of roof collapse in square and circular tunnels with different rock parameters were derived and discussed, which proves to be valid in comparison with the previous work. The influences of different parameters on the shape of collapsing blocks were also discussed.The analytical solutions for predicting the exact shape of collapse mechanisms in shallow tunnels with arbitrary excavation profiles were obtained by virtue of the upper bound theorem of limit analysis and variation principle according to Hoek-Brown failure criterion. The seepage force was included in the upper bound limit analysis, and it was computed from the gradient of excess pore pressure distribution. The seepage was regarded as a work rate of external force. The numerical results of roof collapse in square and circular tunnels with different rock parameters were derived and discussed, which proves to be valid in comparison with the previous work. The influences of different parameters on the shape of collapsing blocks were also discussed.

关 键 词：shallow tunnel collapse mechanism seepage force upper bound limit analysis Hoek-Brown failure criterion 

分 类 号：U452.11[建筑科学—桥梁与隧道工程]