中文摘要：

膨胀软岩巷道围岩黏土矿物含量高、自身强度低、亲水膨胀性强,在复杂地应力和水理作用下极易发生变形失稳。结合小屯矿轨道大巷支护变更工程实践,通过地质调查、现场观测及室内试验等手段分析发现：巷道渗水量大,围岩节理裂隙发育、孔隙率高,膨胀性黏土含量高,水化作用后耐崩解性差都加剧了围岩的变形失稳。针对性地提出以格栅钢架为主体结构的“全封闭格栅钢架＋挂网＋锚杆＋喷射/浇筑混凝土”联合支护体系,通过数值模拟,揭示了全封闭支护设计的整体性优势,并对支护方案的格栅钢架间距和锚杆长度进行优化,制定出适用现场工况的钢架规格参数及其施工工艺流程。同时辅以集水坑降低底板水位,最终以全封闭格栅钢架为主体结构的联合支护体系有效地控制了巷道围岩变形,在小屯煤矿膨胀软岩巷道取得了成功应用。

英文摘要：

Deformation, fracture and instability of surrounding rock occur easily in expansive soft rock roadways due to its high clay mineral contents. Under the hydraulic action and high geostress, the clay minerals will show a strong hydrophilic expansibility and a weak resistance intensity. A case study combining with situ conditions of main haulage roadway in Xiaotun coal mine was performed. After geological surveys, field observations and laboratory tests, we find that the seepage action, weathering action, slaking durability and clay mineral contents all are reasons contributing to the deformation and instability of roadway surrounding rock. A combined support system of Full-closed steel grid flame ＋ Wire mesh ＋ Bolt ＋ Shotcrete/Pouring concrete is put forward in this paper. The superiorities of the full-closed flame design are demonstrated, and the spacing between frames as well as the length of the bolts is optimized by numerical simulation. Meanwhile, catchpit is adopted to govern the water-inrush of roadway floor successfully. Finally, the full-closed steel grid frame-oriented combined support system effectively control the deformation of surrounding rock, therefore has a reference significance to similar expansive soft rock support engineering.