坚硬K2灰岩顶板水压致裂强制放顶设计与应用

Design and Application of Forced Caving for Hard K2 Limestone Roof by Hydraulic Fracturing

【目的】铁新煤业9226工作面回采后端头区域坚硬K2灰岩顶板难以正常垮落,在工作面后方悬露较大空顶区域,威胁工作面作业安全,需要对其进行水压致裂强制放顶处理。【方法】针对9226工作面端头长距离悬顶带来的安全隐患,根据9226工作面坚硬K2灰岩顶板工程地质条件,通过理论计算方法设计9226工作面超前水压预裂参数,确定超前水压预裂实施流程,开展现场试验和观测。【结果】结果表明,水压致裂放顶技术解决了9226工作面后方厚硬石灰岩顶板难以及时垮落的问题,保证了工作面推进速度。【结论】本研究为水压致裂技术在类似条件煤炭开采中的推广应用奠定了基础。

[Purposes]The hard K2 limestone roof in the rear end area of the 9226 working face of Tiexin Coal Industry is difficult to collapse normally,resulting in a large empty roof area hanging behind the working face,which poses a threat to the safety of the working face operation,and it needs to be forced caving by hydraulic fracturing.[Methods]In response to the safety hazards caused by the long-distance suspended roof at the end of the 9226 working face,based on the engineering geological conditions of the hard K2 limestone roof of the 9226 working face,the advanced water pressure pre-splitting parameters of the 9226 working face were designed through theoretical calculation,and the implementation process of the advanced water pressure pre-splitting was determined.Field practice and observation were carried out.[Findings]The results showed that the hydraulic fracturing roof release technology solved the prob⁃lem of difficult timely collapse of the thick and hard limestone roof behind the 9226 working face,ensur⁃ing the advancing speed of the working face.[Conclusions]This study lays the foundation for the promo⁃tion and application of hydraulic fracturing technology in coal mining under similar conditions.