高瓦斯矿井矸石充填沿空留巷支护技术

Coal Rejects Backfill Support Technology of Gob-side Entry Retaining in High Gassy Mine

针对矸石充填沿空留巷围岩变形大的特点,以新阳煤矿2013N工作面沿空留巷为研究对象,采用理论分析的方法对留巷变形量大、变形持续时间长、受采空区顶板周期性垮落影响剧烈的原因进行分析;通过数值模拟的手段分析了沿空留巷施工过程中巷道顶板、两帮及矸石充填体随工作面回采的应力、位移变化规律;采用现场实测的方法揭示了沿空留巷的支护机理。结果表明:沿空留巷的围岩变形分3个阶段:采动影响不明显阶段、采动影响强烈阶段、采动变形稳定阶段。采用锚网索联合支护方式能有效加固煤岩体,防止顶板发生较大离层,增加两帮煤体强度,防止留巷发生大的变形。

According to the high deformation features of the surrounding rock in the coal rejects backfill gob-side entry retaining, taking the gob-side entry retaining of No.2013N coal mining in Xinyang Mine as the study object, a theoretical analysis method was applied to an- alyse the causes of the high deformation value of the gob-side entry retaining,long sustained deformation time, the serious periodical roof falling influence of the goaf.With the numerical simulation means ,the paper analyzed the stress and displacement variation law of the gate- way roof,two sidewall and gob-side entry retaining during the construction process of the gob-side entry retaining.The site observation method was applied to reveal the support mechanism of the gob-side entry retaining.The results showed that the surrounding rock deforma- tion of the gob-side entry retaining could be divided into three stages.The three stages were a mining influence unobvious stage, mining in- fluence serious stage and mining deformation stable stage.The application of the bolt,steel mesh and anchor combined support mode could effectively reinforce the coal and rock mass, prevent large bed separation occurred in the roof, improve coal mass strength of the two side- walls and prevent large deformation occurred in the gob-side entry retaining.