大采高首采面坚硬顶板初采放顶预裂技术研究

Study on pre-cracking technology of initial mining and topping for hard roof in large mining height

紫晟煤业首采区大采高工作面煤层上方厚度为7.5m的灰岩,较为坚硬,在初采过程中较难垮落,为保证工作面初采安全,分析现有煤矿井下坚硬岩层预裂控制技术优缺点以及其适用性,通过理论分析和数值模拟,提出采用双向聚能爆破技术对灰岩坚硬顶板进行提前预裂,解决首采面回采过程难垮落问题。

The limestone with a thickness of 7.5 m above the coal seam of the large mining height working face in the first mining area of Ziyan Coal Industry is relatively hard and difficult to fall during the initial mining process.To ensure the safety of the initial mining face,analyze the existing hard rock formation in the underground coal mine.The advantages and disadvantages of the pre-cracking control technology and its applicability.Through theoretical analysis and numerical simulation,it is proposed to use the two-way energy blasting technology to pre-crack the hard roof of limestone to solve the problem of difficult mining in the first mining face.