富水条件三软煤层沿空巷道支护设计优化

Support design optimization of gob-side entry in water-soaked three-soft coal seam

针对小屯煤矿沿空巷道顶底板岩性松软、沿空煤柱浸水失稳、围岩持续大变形等问题,通过现场围岩变形监测和拉拔试验,分析原有支护条件下围岩的变形特征和破坏原因,并对支护方案进行优化,提出"两帮中空注浆锚杆(锚索)高强预注+顶板高强全锚+底角注浆加固"的支护方案。经现场工业试验巷道的底鼓量、顶板下沉量和两帮移近量分别减少了38%、77%、40%,优化后的支护方案有效地控制了巷道围岩的变形破坏,保证了沿空巷道的稳定性,取得了良好的支护效果。

Aiming at problems of Xiaotun Coal Mine such as fluvial rock in the roof and floor of roadway, destabilization of water-soaked coal pillar in Gob- Side entry, continuous large deformation of surrounding rock, etc., through the surrounding rock deformation monitoring and pull-out test, we analyzed the surrounding rock deformation characteristics under the original support conditions and causes of damage, optimized the support program, and proposed support scheme ： hollow grouting anchor （anchor） high-strength pre-injection for the ribs, high-strength full anchor for the roof, grouting reinforcement for the floor. After implementation of the joint support scheme the floor heave amount was reduced by 38%, roof subsidence by 77%, and two-side-convergence by 40%. With the optimized supporting scheme, the deformation of roadway surrounding rock was effectively controlled.