阳城矿深部复合型软岩大巷破坏机制与支护设计

针对阳城煤矿南翼软岩大巷严重底鼓和断面收缩等非线性流变大变形控制难题,综合采用力学试验、现场测试和理论分析等方法,分析了南翼大巷围岩的地质力学特性和破坏特征;通过建立受二向均布载荷作用下的巷道力学模型,研究揭示了阳城煤矿南翼软岩大巷变形破坏力学机制。结果表明:地应力环境对大巷产生了极为不利的影响;大巷围岩属HJS复合型软岩,节理裂隙发育、松动破坏严重,使得可承载的完整岩层厚度较小是大巷破坏严重的关键因素。基于大巷复杂的破坏机制,提出了以锚注为主体的锚网索喷注联合支护方式,并设计使用了新型的注浆锚索,注浆管+注浆锚索深、浅耦合注浆,取得了良好的现场应用效果,实现了软岩大巷变形的有效控制,为类似巷道工程提供了参考。

Failure mechanism and support design of deep composite soft rock roadway in Yangcheng coal mine

To solve the control problem in a series of nonlinear rheological large deformation phe-nomena such as serious floor heaves and section shrinkage of the south limb soft rock roadway in Yangcheng coal mine, the surrounding-rock geomechanical properties and failure characteristics were analyzed with the methods of mechanical testing, theoretical analysis and field test. By establishing roadway mechanical model under biaxial uniform loading, the deformation and failure mechanism of the south limb soft rock roadway were studied and revealed. The results have shown that ground stress environment has a very adverse effect on the soft rock roadway, the surrounding-rock of the roadway is HJS composite soft rock, and the small complete strata thickness owing to joint fissures and loose dam-ages of the surrounding-rock is the key factor for severe failure of the roadway. Based on the complex failure mechanism of the soft rock roadway, the combined supporting was put forward through bolting,metal net, guniting, and grouting with bolting and grouting support as the main method. In addition, a new grouting cable anchor was designed and applied. Deep and shallow coupling grouting was realized by the grouting bolt and the new grouting cable anchor. Finally practical engineering has shown that the combined supporting was effective and the large deformation of soft rock roadway was effectively con-trolled. The achievement of deformation control of the south limb soft rock roadway in Yangcheng coal mine provided an important reference for the similar roadway project.