坚硬顶板综采工作面爆破放顶技术研究

以胡底矿4304工作面为工程背景,通过数值模拟分析了随工作面推进顶板垮落情况和矿压分布特征,推测出工作面初次来压步距为37m,存在顶板大面积悬露而突然垮落的问题。采用超前深浅孔相结合的松动爆破技术,对工作面顶板进行弱化处理。结果表明：经过爆破处理后,4304工作面直接顶的平均垮落步距为15.4m,小于模拟结果|基本顶沿工作面呈现分段来压的特点,在工作面上部来压步距最大|初采期间未观测到煤壁大范围片帮、煤炮等明显来压现象,且未出现回风巷瓦斯超限问题,爆破放顶效果较好。

Study on the technology of forced roof caving in fully mechanized mining face

Taking the 4304 working face of Changping Mine as the engineering background, the numerical simulation was used to analyze the roof collapse and the distribution of mine pressure with the working face. It is estimated that the initial pressure step of the working face is 37 m, and there is a large area of roof. And suddenly the problem of falling. Using the advanced deep hole loose blasting technology, the top surface of the working face is weakened. The results show that after the blasting treatment, the average stepping distance of the direct top of the 4304 working face is 15.4 m, which is smaller than the simulation result; the basic top is presented along the working surface. The characteristics of the section pressure are the largest in the working face; during the initial mining period, no obvious pressure phenomenon such as coal seams and coal cannons are observed, and there is no problem of gas overrun in the return air passage. the existence of the lava collapse column on the working face and the weakening effect of the blasting are factors that weaken the mine pressure on the working face. The existence of the lava collapse column in the working face and the weakening effect of the blasting are factors that weaken the mining pressure on the working face.