切顶成巷切缝高度优化及矿压显现规律研究

Research on Stress Variation and Manifestation Laws of Surrounding Rock in Top-Cutting and Tunneling

本文以山东某矿为工程背景,综合利用理论分析、数值模拟、现场实践等方法,辅以切顶成巷矿压数据动态监测系统为观测手段,研究基于切顶成巷技术条件下的矿压显现规律。研究结果表明:通过应用FLAC3D数值模拟软件,确定本工作条件下最佳切缝高度为8 m,相对于沿空留巷巷道,切顶成巷巷道围岩基本处于一个较低的应力环境中,说明在顶板实施切顶技术后形成的切缝面有效阻断了应力的传播路径,并且切顶成巷巷帮两侧煤体内的垂直应力峰值有所降低,说明起到了卸压的效果。对比沿空留巷巷道垂直应力峰值位置,位于切缝侧的成巷巷道垂直应力峰值位置向更深部进行了转移,工作面直接顶初次来压步距综合约为16 m。

This article takes a coal mine in Shandong Province as the engineering background.Through the comprehensive use of theoretical analysis,numerical simulation,on-site practice,and the dynamic monitoring system of roof-cutting roadway pressure data,it studies the manifestation laws of strata pressure based on the technology of roof-cutting roadway.The research results show that,by applying FLAC3D numerical simulation software,the optimal height of the cutting slot under the working conditions is determined to be 8 meters.Compared to the goaf roadway,the surrounding rock of the roof-cutting roadway is in a lower stress environment.This indicates that the cutting slot formed after implementing the roof-cutting technology effectively blocks the stress propagation path,and the vertical stress peak values inside the coal body on both sides of the roof-cutting roadway are reduced,indicating the effect of stress relief.Compared with the position of the vertical stress peak in the goaf roadway,the position of the vertical stress peak in the roof-cutting roadway has shifted deeper.The comprehensive initial support step distance of the working face is about 16 meters.