首采工作面初采强制放顶方案设计及应用

Design and application of forced caving on first mining face

针对某煤矿2-1煤层21102工作面顶板坚硬、不易垮落的问题,运用理论分析、数值模拟、现场实践方法,计算出首采工作面顶板人工处理的垂直高度为14 m,该顶板砂岩石中形成的粉碎圈和裂隙圈半径分别为0.2,4.8 m,通过数值模拟确定合理的炮孔间距为10 m,最终确定采用深孔预裂爆破强制放顶的方案。现场应用表明,此次深孔爆破强制放顶后顶板未出现大量涌水及工作面设备、设施损坏现象,爆破及施工过程也未发生任何安全事故,爆破后采空区基本顶有效预裂,且充填率达到了预期目的,来压强度不大。

Aimed at the problem of hard and difficult roof in Ⅱ1 coal seam of 21102 working face of some coal mine,the vertical height of the roof was calculated by theoretical analysis, numerical simulation and field practice. The radius of crushing circle and fracture cir-cle formed in the roof are 0. 2 m and 4. 8 m, respectively. The reasonable spacing of blasting holes is 10 m through numerical simula-tion. Finally,the scheme of deep hole blasting was adopted. The field application shows that,there is not a lot of gushing water,damaged facilities and equipment on working face,and any safety accidents appeared in the blasting and the construction process after the deep hole blasting. The main roof of gob was effectively presplit, filling rate has reached the expected purpose, the strengthen of roof weighting is not big.