大强煤矿深井软岩马头门支护技术

以大强煤矿副立井马头门硐室为工程背景,根据工程地质条件和围岩特点,借助FLAC3D有限差分程序进行传统支护下的数值计算。结果表明,该硐室采用传统的锚网喷＋锚索＋普通混凝土支护形式,出现围岩变形明显、应力集中程度大、硐室围岩整体失稳破坏的情况。为解决这一问题,结合软岩工程力学理论及室内物化实验结果,分析马头门硐室的破坏机理,提出恒阻大变形锚网索＋底角锚杆＋柔层桁架耦合支护的力学控制对策。实践表明,新型支护技术有效地控制了深井软岩马头门硐室围岩的大变形破坏,取得了良好的支护效果,具有推广应用价值。

Support technology designed for soft rock in deep coal in Daqiang coal mine

This paper introduces the numerical calculation of traditional support using FLAC3D finite difference program, conditioned by its engineering geological conditions and surrounding rock characteris- tics occurring in the auxiliary shaft ingate chamber of Daqiang coal mine. The result shows that conven- tional support form, a combination of spray anchor net, anchor rope, and ordinary concrete, results in significant deformation of surrounding rock, greater stress concentration, and overall instability of sur- rounding rock of chamber, as in the case of shaft ingate chamber of Daqiang coal mine. The solution fol- lows from an analysis of the failure mechanism of ingate chamber, combined with soft rock engineering mechanics theory and indoor physical and chemical test results and the development of the mechanical control countermeasures marked by the combined application of the constant-resistance large deformation bolt-net-anchor, bottom comer anchor, and flexible layer truss coupling support. The practice shows that the new support technology affords an effective control of large deformation of the ingate chamber in deep soft rock, yields a better support effect, and promises a wider application.