摘要
针对深孔顶板水压致裂防冲施工技术参数选择及效果检验的难题,通过理论分析和现场测试探讨了3种不同顶板定向水压致裂防治冲击地压的类型及机理,采用钻孔窥视、应力监测、微震监测等多种检测手段对比分析了压裂前后的防冲效果。研究得出根据深孔顶板水压预裂施工位置及工作面的对应关系,可将顶板水压致裂防冲分为防治煤柱冲击、防治工作面冲击和防治初末采期间工作面冲击3种类型,现场对比分析得出巷道双侧压裂卸压效果优于单侧压裂,顶板压裂促使微震事件向工作面中部转移,工作面周期来压步距和来压期间的动载系数降低,巷道变形量和锚杆(索)应力增量随工作面推进波动上升,但变化幅值和增长趋势明显小于未压裂段。此外,间隙性顶板水压致裂人为在高位顶板制造了空白卸压区,破坏了顶板连续变形和能量传递,工作面进出该区域往往易造成动压显现的发生,为此类工程条件下顶板定向水压致裂参数选取和防冲效果验证提供理论依据和工程指导。
In view of the selection of technical parameters and the effect inspection of rockburst control in the process of deep-hole roof hydraulic fracturing, theoretical analysis and field tests have been carried out to discuss the types and mechanisms of three different deep-hole roof directional hydraulic fracturing on rockburst control, and the effect of rockburst pre and post fracturing have been tested through contrast analysis with borehole peeping, stress monitoring and microseismic monitoring. It has been concluded that according to the corresponding relationship between the construction position of deep-hole roof hydraulic and the working face, rockburst prevention in the deep-hole roof hydraulic fracturing can be divided into three types: prevention of coal pillar rockburst, prevention of working face rockburst, and prevention of working face rockburst during initial and final mining. Field comparative analysis shows that the pressure relief effect in double-side fracturing of roadway was better than that of single-side fracturing. Microseismic events can be transferred by the roof fracture to the middle of working face and the periodic weighting length and dynamic load coefficient during weighting of working face can accordingly be reduced. The deformation amount of roadway and stress increment of bolt(cable) wavelike rises with face advance, but the change amplitude and growth trend were obviously smaller than those of unfractured section. In addition, the intermittent roof hydraulic fracturing artificially creates a blank pressure relief area in the high-level roof, which will damage the continuous deformation and energy transmission of the roof. As a result, the rockburst will easily occur when working face is advanced in and out this area. The research has provided a theoretical basis and practical guidance in selection of parameters and the effect test in the process of deep-hole roof hydraulic fracturing under similar engineering condition.
作者
赵善坤
张广辉
柴海涛
苏振国
刘毅涛
张修峰
ZHAO Shankun;ZHANG Guanghui;CHAI Haitao;SU Zhenguo;LIU Yitao;ZHANG Xiufeng(Mine Safety Technology Branch of China Coal Research Institute,Beijing 100013,China;State Key Laboratory of Coal Mining and Clean Utilization of China Coal Research Institute,Beijing 100013,China;Wushen Country Mengda Mining Industry Co Ltd,Ordos,Inner Mongolia 017305,China;Yanzhou Coal Ordos Energy and Chemical Co Ltd,Ordos,Inner Mongolia 017010,China)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2019年第6期1247-1255,共9页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(51874176,51574150,51674143)
国家重点研发计划项目(2017YFC0804203)
国家油气重大专项项目(2016ZX05045003-006-002)
天地科技股份有限公司科技创新创业资金专项项目(2018-TD-QN004)
关键词
定向水压致裂
冲击地压
防冲机理
多参量
效果检验
directional hydraulic fracturing
rockburst
mechanism of rockburst prevention
multi-parameter
effect test
