近距离坚硬顶板巷道水力控顶理论及其应用研究
The hydraulic roof control theory and its application in contiguous hard roof roadway
张兆一1
作者信息
- 1. 煤矿灾害防控全国重点实验室,重庆 400037;中煤科工集团重庆研究院有限公司,重庆 400037
- 折叠
摘要
为研究近距离坚硬顶板巷道水力控顶理论,通过理论分析和数值模拟研究了水力化控顶卸压时煤层载荷、巷道应力分布规律,揭示了水力化控顶卸压对巷道围岩稳定性的影响机制,阐明了该技术的工艺流程.研究结果表明:81403 回风巷道未开掘时,工作面周期来压步距 19 m,直接顶厚度4.84 m,基本顶厚度10.64 m,内应力区范围5.2 m;远离81401 采空区侧的15#煤层荷载与巷道开掘和单向切顶后相比分别降低了20%、15%;现场观测切顶钻孔试验区域巷道高度收敛率为33.7%、巷道宽度收敛率为23.0%,巷道高度收敛率较对比区域降低39%、宽度收敛率较对比区域降低 32%.采用单侧高压磨料射流钻孔切顶能使顶板岩层及时垮落,切断顶板岩层间应力传递途径,能有效改善巷道围岩应力状态,减少工作面回采巷道后期顶底板及两帮变形量,降低巷道维护难度.
Abstract
In order to study the hydraulic roof control theory in contiguous hard roof roadway,the distribution of coal seam load and roadway stress during hydraulic roof control and pressure relief were investigated through theoretical analysis and numerical simulation.The mechanism of the influence of hydraulic roof control and pressure relief on the stability of roadway surrounding rock has been revealed,and the associated technological process has been elucidated.The results show that when the 81403 return airway is not excavated,the periodic weighting step of the working face is 19 m,the immediate roof thickness is 4.84 m,the main roof thickness is 10.64 m,and the range of internal stress zone is 5.2 m.Compared to the excavation of the roadway and the single roof cutting,the load of No.15 coal seam away from the side of 81401 goaf is reduced by 20%and 15%,respectively.The convergence rate of roadway height and width in the on-site observation of the top cutting drilling test area is 33.7%and 23.0%,respectively.The convergence rate of roadway height and width is 39%and 32%lower than those in the comparison area.The use of unilateral high-pressure abrasive jet drilling and roof cutting can timely collapse the roof rock layer,cut off the stress transmission path between the roof rock layers.Therefore,it can effectively improve the stress state of the surrounding rock of the roadway,reduce the deformation of the roof,floor,two sides of the roadway in the later stage of mining,and the difficulty of roadway maintenance.
关键词
近距离/坚硬顶板/水力控顶/数值模拟/力学模型/工业试验Key words
close range/hard roof/hydraulic roof control/numerical simulation/mechanical model/industrial trial引用本文复制引用
基金项目
天地科技股份有限公司科技创新创业资金专项(2022-2-TD-ZD008)
出版年
2024
NETL
NSTL
万方数据