泥质胶结砂岩切眼顶板支护结构稳定性分析

Stability analysis of support structure of cutting roof with argillaceous cemented sandstone roof

以万利一矿综采207工作面切眼遇泥质胶结砂岩条件为背景,通过力学理论分析和现场实践对泥质胶结砂岩切眼顶板支护结构稳定的工程安全问题进行分析,并基于层状梁结构模型分析切眼顶板锚索悬吊承载稳定性。结果表明:泥质胶结砂岩顶板呈现层间黏结力差,易发生错动离层的失稳特征,顶板锚杆锚固支护对层间错动起到抑制作用,锚索悬吊能够提供可靠支护反力和减小顶板跨度,并对顶板锚固体的稳定性起到增益作用。结合现场条件提出"预应力钢锚杆+钢筋网+锚索+钢带+顶板疏导水"的切眼巷道支护对策,现场工程实践表明切眼巷道顶板控制效果良好且满足安全生产要求。

Taking the condition of mud-cemented sandstone encountered in the 207 working face of Wanli No.1 Mine as the background,based on the mechanical theory analysis and field practice,the engineering safety problems of the stability of the open-cut roof support structure of mud-cemented sandstone are analyzed,and the suspension bearing stability of the open-cut roof anchor cable is analyzed based on the layered beam structure model.The analysis shows that the mud-cemented sandstone roof presents the characteristics of poor interlayer bonding force,which is prone to dislocation and separation of layers.Roof bolt anchoring support can inhibit the dislocation between layers,and anchor cable suspension can provide reliable support reaction force and reduce the span of the roof,and play a role in enhancing the stability of the roof anchor solid.Combined with the field conditions,the support strategy of"pre-stressed steel bolt+steel mesh+anchor cable+steel belt+roof drainage"was put forward.The field engineering practice shows that the roof control effect of open-cut roadway is good and meets the requirements of safety production.