Upper bound limit analysis of roof collapse in shallow tunnels with arbitrary cross sections under condition of seepage force
来源期刊：中南大学学报(英文版)2014年第11期
论文作者：杨小礼 QIN Chang-bing(覃长兵)
文章页码：4338 - 4343
Key words：shallow tunnel; collapse mechanism; seepage force; upper bound limit analysis; Hoek-Brown failure criterion
Abstract: 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.
YANG Xiao-li(杨小礼), QIN Chang-bing(覃长兵)
(School of Civil Engineering, Central South University, Changsha 410075, China)
Abstract: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.
Key words:shallow tunnel; collapse mechanism; seepage force; upper bound limit analysis; Hoek-Brown failure criterion
