伊田煤业坚硬顶板水力压裂弱化技术研究

Study on Hydraulic Fracturing Weakening Technology of Hard Roof in Yitian Coal Industry

为解决伊田煤业2203工作面推进过程中坚硬顶板不易垮落、悬顶面积大进而引起矿压显现剧烈的问题,提出了分段水力压裂弱化顶板技术。通过数值模拟结合现场实际条件确定同一钻场内布置3个钻孔,且压裂裂缝半长应大于41.6 m,压裂时长应在30 min以上。实施分段水力压裂技术后,坚硬顶板能够及时垮落,且工作面来压前的平均支架循环末阻力降低了4.39%,周期来压时的平均支架循环末阻力降低了9.13%,动载系降低了12.8%。

In order to solve the problem that the hard roof is not easy to collapse and the suspended roof area is large,which leads to severe mine pressure in the advancing process of the 2203 working face in Yitian Coal Mine,the technology of weakening roof by sectional hydraulic fracturing is put forward.Through numerical simulation combined with the actual conditions in the field,it is determined that three boreholes are arranged in the same drilling field,and the half length of the fracturing crack should be more than 41.6 m and the fracturing time should be more than 30 min.After the implementation of the sectional hydraulic fracturing technology,the hard roof can collapse in time,and the average support cycle end resistance before the pressure of the working face is reduced by 4.39%,the average support cycle end resistance under periodic pressure is reduced by 9.13%,and the dynamic load system is reduced by 12.8%.