高瓦斯煤层切顶卸压无煤柱自成巷技术应用研究

Application research on technology of non-pillar gob-side entry retaining formed by roof cutting and pressure release in high gas coal seam

针对传统的沿空留巷技术多是采用靠采空区一侧巷旁充填等方法进行护巷,存在成本较高、施工工艺复杂、施工进度较慢等问题,以杜儿坪煤矿高瓦斯煤层62711工作面为研究对象,研究了切顶卸压无煤柱自成巷技术,从预裂切缝关键参数设计、留巷补强加固支护、采空区挡矸支护、瓦斯安全管理方法等方面详细分析了切顶卸压无煤柱自成巷工艺流程,并在工作面进行了矿压监测分析。分析结果表明,杜儿坪煤矿采用切顶卸压无煤柱自成巷技术实现了对采场的卸压作用,成功保留了62711工作面轨道运输巷作为下一邻近工作面的胶带运输巷使用,明显提高了煤炭回采率,缓解了煤矿采掘衔接紧张,避免了残留煤柱导致的相关矿山灾害;“Y”型通风方式的使用有效地解决了工作面上隅角瓦斯积聚问题。

In view of problems of high cost, complex construction technology and slow construction progress existed in traditional gob-side entry retaining technology which mostly adopts method of filling at the side of goaf to protect the roadway, the technology of non-pillar gob-side entry retaining formed by roof cutting and pressure release in high gas coal seam was studied taking 62711 working face in high gas coal seam of Duerping Coal Mine as research object. The technical process of the technology of non-pillar gob-side entry retaining formed by roof cutting and pressure release was analyzed in detail from the aspects of key parameters design of pre-splitting and cutting joints, entry retaining reinforcement and support, gangue retaining support in goaf, gas safety management method, and rock pressure monitoring was carried out on the working face. The analysis results show that application of the technology of non-pillar gob-side entry retaining formed by roof cutting and pressure release in Duerping Coal Mine realizes pressure release effect on the stope, and successfully keep track transportation roadway of 62711 working face as the next adjacent working face belt transportation roadway, which obviously improves coal recovery rate, relieve the tension between coal mining and tunneling, and avoids mine disasters caused by residual coal pillars. In addition, the use of "Y" type ventilation mode effectively solves the problem of gas accumulation in the upper corner of the working face.