摘要
针对凌志达矿15218工作面坚硬顶板条件回采过程中导致的巷道变形严重问题,采用理论分析、数值模拟与现场监测相结合方法,系统研究了坚硬顶板切顶卸压及巷道支护方法。结果表明:顶板基本顶K2灰岩为关键层,由于顶板泥岩与K2灰岩总厚度达8.12 m,应保证切顶高度大于8.12 m;对工作面顶板实施切顶卸压后,能够在一定程度上切断高应力传导路线,使应力发展不会朝向煤柱及临近工作面巷道,有利于巷道及煤柱的稳定,对坚硬顶板实施切顶卸压可以取得良好的卸压效果,数值模拟确定合理切顶高度与角度分别为9 m与15°。研究提出了在巷道顶板中部实施超前预裂爆破切顶卸压方法,以及“锚杆+金属网+钢筋梯子梁+锚索”的巷道联合支护技术。通过现场实践,顶板下沉量降低了43.1%,底板底鼓量降低了31.5%,煤柱帮移近量降低了36.1%,回采帮移近量降低了36.2%,巷道变形得到了良好控制。
Aiming at the serious roadway deformation caused by the hard roof condition mining in 15218 working face of Lingzhida Mine,the method of roof cutting and unloading and roadway support are systematically studied by combining theoretical analysis,numerical simulation and field monitoring.The results show that the basic roof K2 limestone is the key layer.Since the total thickness of roof mudstone and K2 limestone is 8.12m,the cutting height should be ensured to be greater than 8.12m.After cutting and relieving pressure on the working face roof,the high-stress conduction route can be cut off to a certain extent,so that the stress development will not be towards the coal pillar and the roadway near the working face,which is conducive to the stability of the roadway and the coal pillar.The implementation of cutting and relieving pressure on the hard roof can achieve good pressure relief effect.The reasonable cutting height and Angle are determined as 9m and 15°respectively by numerical simulation.In this paper,the method of cutting and unloading the roof by pre-split blasting is put forward in the middle of the roadway roof,and the roadway combined support technology of"bolt+metal net+steel ladder beam+anchor cable"is proposed.Through the field practice,the roof subsidence is reduced by 43.1%,the floor heave is reduced by 31.5%,the coal pillar side displacement is reduced by 36.1%,the mining side displacement is reduced by 36.2%,and the roadway deformation is well controlled.
作者
张银
ZHANG Yin(Shanxi Lingzhida Coal Industry Co.,LTD.,Changzhi046606,China)
出处
《煤矿现代化》
2024年第1期98-102,108,共6页
Coal Mine Modernization
关键词
切顶卸压
坚硬顶板
预裂爆破
支护
关键层
top cutting pressure relief
hard roof
presplit blasting
support
critical layer
