摘要
文中以某隧道碳质千枚岩地层为工程背景,采用FLAC3D-PFC3D耦合模型,分析双层钢拱支护、弱化靠近开挖面的钢拱和弱化远离开挖面的钢拱形支护等方案。结果表明,双层钢拱能很好地减小软岩的大变形。当其中一个钢拱的刚度减弱时,支架控制变形的能力减弱,但在控制变形方面仍表现出可靠的性能,且H3和H4两种支护下的外围累积收敛曲线并不重合,这说明当采用两层刚度不同的钢拱架进行支撑时,将刚度较小的钢拱架放在外侧更为合理。
The article takes the carbonaceous phyllite formation of a certain tunnel as the engineering background,and uses the FLAC3D-PFC3D coupling model to analyze the schemes of double-layer steel arch support,weakened steel arch near the excavation face,and weakened steel arch support far away from the excavation face.The results indicate that double-layer steel arches can effectively reduce large deformations in soft rocks.When the stiffness of one of the steel arches weakens,the ability of the support to control deformation weakens;However,it still demonstrates reliable performance in controlling deformation.And the peripheral cumulative convergence curves under H3 and H4 support do not coincide,indicating that when using two layers of steel arches with different stiffness for support,it is more reasonable to place the steel arch with lower stiffness on the outer side.
作者
刘志鹏
Liu Zhipeng(China Railway 1lth Bureau Group First Engineering Co.Ltd.,Xiangyang,Hubei 441100)
关键词
高地应力
碳质千枚岩地层
铁路隧道
失稳
支护
High ground stress
Carbonaceous phyllite formation
Railway tunnel
Instability
Support
