膨胀应力作用下复合顶板巷道围岩支护研究

Study on surrounding rock support of composite roof roadway under expansion stress

针对澄合矿区复合顶板管理难度大,巷道支护困难,严重制约矿井安全开采这一问题,以山阳煤矿5号煤层1501回风巷为工程背景,对复合顶板软岩巷道的破坏机理及支护问题展开了研究。首先通过物理力学试验,得到顶板各岩层的物理参数,然后采用现场实测和理论分析的方法,分析复合顶板的应力分布特征,从而构建山阳煤矿巷道的复合顶板力学模型,最后运用数值模拟和现场实测的方法验证支护方案的可行性。研究结果表明,矿井复合顶板上部砂质泥岩为膨胀岩,最大膨胀率为42.3%,最大膨胀应力为198.2k Pa;中粒砂岩层K4为关键岩层;提出的顶板采用全锚索支护,巷帮采用金属网+钢带+锚杆支护的支护方案,经过数值模拟和现场实测的验证,该方案可满足现场生产需求。研究成果可为类似地质条件的巷道支护提供参考。

Faced with significant challenges of composite roof management and roadway support in the Chenghe mining area,which severely hinder safe mining operations,this study utilized the 1501 return air roadway of the No.5 coal seam in Shanyang Coal Mine as a case study to explore the failure mechanisms and support strategies for soft rock roadways beneath composite roofs.By conducting physical and mechanical experiments,the study identified the physical parameters of each rock layer within the roof and analyzed the stress distribution character-istics of the composite roof through both field measurements and theoretical analysis.This process led to the de-velopment of a comprehensive mechanical model for the composite roof of the roadway in Shanyang Coal Mine.The study proposed a support scheme that employs full anchor cable support for the roof and a combination of metal mesh,steel straps,and anchor rods for the roadway sides.The effectiveness of this scheme was then vali-dated through numerical simulation and field measurements.The results indicated that the sandy mudstone layer in the upper part of the mine's composite roof is an expansive rock with a maximum expansion rate of 42.3%and a maximum expansion stress of 198.2 kPa,making the medium-grained sandstone layer K4 a key layer.The pro-posed support scheme successfully meets on-site production needs,proving the feasibility of this new approach and offering a valuable reference for managing similar geological conditions in other mines.