摘要
针对西山矿区官地矿在沿空留巷时,存在开采深度较大、顶板破碎,留巷后顶板形变量大,且煤帮被挤压凸出、底鼓严重的难题,以官地矿12607综采工作面为工程背景,开展了切顶卸压柔模墙支护技术研究。在超前工作面沿空留巷区域借助双向聚能爆破技术对顶板开展预裂爆破,减少顶板应力;伴随工作面持续开采,在距工作面后方煤壁一定区域,构筑混凝土柔模墙支护巷旁,达到有效支撑顶板的目的。现场实践结果发现:处于钻孔内不同深度处存在2条发育较明显的裂缝,说明预裂爆破具有良好的切顶卸压效果;顶板深部和浅部的最大离层量分别为19 mm和7 mm,巷道顶板支护效果良好;两帮移近量和顶底板移近量分别为486 mm和429 mm,巷道围岩变形处于可控区间内,发挥良好的留巷效果。
In Guandi Coal Mine of Xishan mining area,there are some problems such as large mining depth,broken roof,large roof shape variable after roadway retention,extrusion of coal wall and serious floor heave.Taking 12607 fully-mechanized mining face of Guandi Coal Mine as the engineering background,the research on roof cutting pressure relief flexible mold wall support technology is carried out.In the goaf retaining area of advance working face,the bidirectional shaped charge blasting technology is used to carry out pre-split blasting on the roof to reduce the stress of the roof.With the continuous mining of the working face,concrete flexible form wall is constructed to support the roadway side in a certain area away from the coal wall behind the working face to achieve the purpose of effectively supporting the roof.The field practice results show that there are two obvious fractures at different depths in the borehole,indicating that the pre-split blasting has a good effect of cutting the top and relieving pressure.The maximum separation amount of deep and shallow roof is 19 mm and 7 mm,respectively.The roof support effect is good.The displacement of the two sides and the displacement of the top and floor are 486 mm and 429 mm,respectively.The deformation of the roadway surrounding rock is within the controllable range,and the roadway retention effect is good.
作者
朱云龙
ZHU Yunlong(Guandi Coal Mine,Xishan Electric Coal in Shanxi Coking Coal,Taiyuan 030000,China)
出处
《煤》
2023年第3期4-8,共5页
Coal
基金
国家自然科学基金项目(51804114)
国家自然科学基金—面上项目(2018-09571)。
关键词
沿空留巷
预裂爆破
切顶卸压
柔模墙支护
围岩变形
gob-side entry
precracking blasting
top cutting pressure relief
flexible mold wall support
surrounding rock deformation
