关于隧洞围岩破坏特征的连续-离散耦合分析

为探究不同侧压系数下断面形状对隧洞破坏特征的影响,基于齐热哈塔尔地区地质条件,构建连续-离散耦合数值模型,从洞室围岩塑性区演化、洞室围岩位移及裂纹发育状态进行探讨.结果表明:断面形状相同时,随着侧压系数的增加,洞室顶底板塑性区变化较为明显,且位移集中区域由两帮转移至顶底板;洞室顶底板始终为拉剪复合破坏,而两帮则随着侧压系数的增加由张拉破坏变为拉剪复合破坏;侧压系数一定时,圆形断面洞室破坏程度最小.

Continuous - discrete Coupling Analysis of Tunnel Surrounding Rock Failure Characteristics

To explore the influence of section shape under different lateral pressure coefficients on tunnel failure characteristics, based on geological conditions in Qirehataer area, a continuum - discrete coupling method was established, then the evolution of plastic zone, displacement and crack development status of surrounding rock were discussed. The results show that under the condition of same section shape,with the increase of the lateral pressure coefficient, the plastic zone of the roof and floor of the opening changes obviously, and the displacement concentrated area shifts from the two sides to the roof and floor. The roof and floor of the opening is always the composite failure of tension and shear, while the two sides change from the failure of tension to composite failure of tension and shear with the increase of lateral pressure coefficient. Under the same lateral pressure coefficient, the circular section opening damage is least.