沿空切顶留巷围岩变形规律分析

Analysis on Deformation Evolution of Surrounding Rock in Gob-side Entry Retaining by Roof Cutting

基于切顶卸压自动成巷技术原理,以大隆矿二水平南一1401工作面为研究对象,通过矿压监测系统的数据收集及现场测量记录,对工作面留巷段围岩压力分布及形变规律进行了分析。工作面沿空留巷段围岩变形规律分为4个阶段:工作面前方20 m时,围岩出现缓慢运动;工作面后方0~70 m,围岩运动较剧烈;工作面后方70~190 m,围岩运动逐渐趋于稳定;工作面后方190 m,巷道围岩进入稳定状态。随综采工作面的推进,恒阻锚索应力快速增长阶段超前于顶板离层快速增长阶段;恒阻锚索应力进入稳定阶段滞后于顶板离层稳定阶段。结合矿压监测及现场情况,确定了1401工作面回收“架后临时支护”的安保距离为200 m,回撤后成巷效果良好。

Based on non-pillar mining technology by roof cutting and pressure release,regard the second lever S1-1401 working face of Dalong mine as the research object and analyses the pressure of surrounding rock and deformation evolution by data collection of pressure monitoring system and measurement results.Deformation evolution of surrounding rock in gob-side entry retaining may be divided into four stages.The first-stage,the slow-moving of surrounding rock is 20 m in front of working face.In the rear of the working face,the 0-70 m range is the intense stage of the surrounding rack movement.In the rear of the working face,the 70-190 m range is the section stage of the gobside entry retaining where the surrounding rack movement is slow.After the distance of the working face exceeds 190 m,the surrounding rock movement tends to be sable.The rapid growth stage of constant anchor cable stress is earlier than roof separation.And the stabilization stage of constant anchor cable stress is delayed than roof separation.