深埋弱胶结软岩巷道变形破坏规律与控制对策

为研究深埋弱胶结软岩巷道的变形破坏规律并确定合理的控制对策,以余吾煤矿南翼总回风巷工程为例,通过改变应变软化模型参数来反映弱胶结软岩的泥化以及膨胀特征,对巷道掘进过程中围岩的应力、变形以及破坏规律展开数值分析,并在此基础上提出了锚喷+注浆+反底拱联合支护控制对策。研究结果表明:常规锚喷支护条件下,深埋弱胶结软岩巷道顶底板以及两帮围岩的径向位移将在巷道向前掘进24 m后达到734.2、490.3、549.6 mm,同时,它们的松动区深度将分别增至5.6、2.8、3.0 m,而塑性区深度则扩展至9.5、8.8、13.7 m;而采用锚喷+注浆+反底拱联合支护后,巷道围岩径向位移和塑性区深度将分别减小91%~94%和71%~74%,且达到稳定的时间也大大缩短。

Deformation failure law and control countermeasures of deep buried weakly cemented soft rock roadway

In order to study the deformation-failure law of deep buried weakly cemented soft rock roadway and determine reasonable control countermeasures, taking the south main return laneway of Yuwu Coal Mine as an example, the strain softening model parameters were adjusted to reflect the argillization and volume expansion characteristics of weakly cemented soft rock. The stress, deformation and failure evolution of surrounding rock during roadway excavation were numerically analyzed. On this basis,the combined support control countermeasure of “bolt-shotcrete + grouting + inverted arch”was obtained. The results show that the radial displacement of roof, floor and two sides of surrounding rock in deep buried weakly cemented soft rock roadway will reach 734.2 mm, 490.3 mm and 549.6 mm after tunneling 24 m forward. At the same time, the depth of loose zone will increase to 5.6 m, 2.8 m and 3.0 m respectively, while the depth of plastic zone will expand to 9.5 m, 8.8 m and 13.7 m respectively.After adopting the combined support of “bolt-shotcrete + grouting + inverted arch”, the radial displacement and plastic zone depth of roadway will be reduced by 91%-94% and 71%-74%, respectively, and the time to reach stability is greatly shortened.