薄煤层坚硬顶板沿空留巷防漏风柔性支护技术

Technology of Flexible Supporting for Air Leakage Prevention in Thin Coal Seam Gob- side Entry Retaining with Hard Roof

为解决薄煤层坚硬顶板条件下沿空留巷内新鲜风漏向采空区,引起采空区发火的问题,建立了坚硬顶板沿空留巷力学结构模型,提出矸石带+钢筋+喷浆的巷旁柔性支护方式,并采用实验室试验的方法验证了该支护方式的支护效果,同时在姜家湾煤矿2109巷道进行现场试验。结果表明:矸石带+钢筋+喷浆的巷旁柔性支护方式具有较好的可缩性,在顶板早期运动阶段,允许顶板产生一定变形释放压力;而在后期运动阶段,喷浆材料能较好地附着在支护体表面,顶底板、两帮最大移近量分别为230、170 mm,巷道内CO含量为0,消除了采空区发火的隐患。

In order to solve the problem of fresh air in gob-side entry retaining leaked to goal and caused spontaneous combustion with hard roof, mechanical structure model of gob-side entry retaining under hard roof was built, flexible supporting technology with gangue pack and rebar with guniting was proposed, the supporting effect was verified by test methods, and field test was conducted in No.2019 roadway of Jiangjiawan Coal Mine.The results showed that flexible supporting technology with gangue pack and rebar with guniting had great compres- sibility, which could release part of roof pressure in the early stage of roof movement, and gunite material could be better attached to the surface of flexible supporting in the later stage.The roof-to-floor convergence was 230 mm and rib-to-rib convergence was 170 mm and the content of CO in roadway was 0, the risk of spontaneous combustion in goaf was eliminated.