摘要
针对目前煤矿常用的超前钻孔水力压裂切顶卸压手段无法良好的处理高厚度的坚硬复合顶板,基于煤矿井下多点拖动式裸眼分段压裂成套装备,形成了煤矿井下复合坚硬顶板超长钻孔分段压裂区域弱化解危工艺技术。通过“高-低”位定向长钻孔分段水力压裂的实施,使基本顶提前垮落触矸,对工作面顶板形成有效支撑,避免冲击地压的发生。并且在鄂尔多斯矿区采用煤矿井下定向长钻孔分段压裂的方法开展超前区域弱化解危治理,工程实践证明防治效果显著:在压裂过程中能够在岩体内部形成宏观裂隙与微观裂隙沟通的立体缝网,上覆岩层能够充分垮落,使其更快达到充分采动状态,降低上覆岩层悬顶达到极限跨距后突然失稳对工作面形成动载荷的风险,极大程度上降低了采动影响区域能量释放强度、周期来压强度和煤体内部超前应力峰值,有效减缓巷道变形。
The effect of commonly used roof cutting pressure relief method in coal mine, using advance drilling hydraulic fracturing, is unfavorable for thick and hard composite roof. Based on the multi-point drag-type open-hole stage fracturing complete set equipment in coal mine, the technology of weakening and defusing the danger in the fractured zone of the ultra-long drilling hole with hard composite roof is formed. Using the high-low directional long drilling segmented hydraulic fracturing, the basic roof can collapse and contact the gangue in advance, which forms effective support to the working face roof, and avoids the rockburst. In addition, the method was adopted in Ordos mining area, to regionally weaken the roof in advance, and the effect was remarkable. In the fracturing process, a three-dimensional fracture network was formed in the rock mass to communicate macro and micro fractures, and the overburden rock fully collapsed, so that it reached the full mining state faster, and reduced the risk of dynamic load on the working face caused by sudden instability of overburden rock roof after reaching the limit span, which greatly reduced the energy release intensity, periodic weighting intensity and the leading stress peak value in the coal body, and effectively slowed down the roadway deformation.
作者
吕玉磊
郑凯歌
白俊杰
LYU Yu-lei;ZHENG Kai-ge;BAI Jun-jie(Wushenqi Mengda Minging Co.,Ltd.,Ordos 017000,China;China University of Mining and Technology,Xuzhou 221116,China;China Coal Technology and Engineering Xi’an Research Institute(Group)Co.,Ltd.,Xi’an 710000,China)
出处
《煤炭工程》
北大核心
2022年第10期68-74,共7页
Coal Engineering
关键词
冲击地压
定向长钻孔
水力压裂
坚硬复合顶板
超前卸压
rockburst
directional long borehole
hydraulic fracturing
hard composite roof
advance pressure relief
