坚硬顶板水压致裂控制理论与成套技术

发布时间：2018-03-19 08:50

本文选题：采矿工程　切入点：坚硬顶板　出处：《岩石力学与工程学报》2017年12期 　论文类型：期刊论文

【摘要】：煤矿坚硬顶板具有硬度大、整体性好、分层厚度大等特点,导致诸多围岩控制与安全难题。水压致裂可改造顶板岩体结构,控制工作面顶板的冒落;提出坚硬顶板水压致裂控制的理论与成套技术框架。采用真三轴实验系统等研究揭示水压裂缝的扁椭球体典型形态和空间转向扩展形态,给出围压主应力差、排量、层面与原生裂隙等对水压裂缝扩展的影响规律,考虑围岩的应力应变状态与控顶效果,阐明定向压裂临空坚硬悬顶的断顶线位置适当内错煤柱的原理。给出采动岩体水压致裂的时空关系及确定方法。针对裂缝形态的控制要求,提出定向水力割缝致裂等系统的控制致裂方法,在此基础上研制煤矿井下高压(60 MPa)水压致裂的成套装备。针对不同类型工程特点,控制水压主裂缝扩展、翼型裂纹扩展和吸水湿润作用,使顶板及时充分冒落,实现围岩弱化、应力转移、诱导矿压破煤等功能。研发了工作面端头悬顶、切眼及中部坚硬顶板、坚硬顶煤弱化、综放面初采瓦斯、临空巷道冲击地压和大变形等控制成套工艺技术。成套技术与装备已在大同矿区、神东矿区等推广应用。与传统爆破弱化顶板相比,水压致裂弱化顶板管理简单、扰动小、安全性高、工程量少、作用范围大、控制距离远,且经济成本不到其1/10,在深部开采中更具有优势。
[Abstract]:The hard roof of coal mine has the characteristics of high hardness, good integrity and large stratification thickness, which leads to many problems in the control and safety of surrounding rock. The hydraulic fracturing can transform the roof rock mass structure and control the roof caving in the working face. A theoretical and complete set of technical framework for hydraulic crack control of hard roof is presented. The typical shape of flat ellipsoid and spatial steering extension of hydraulic crack are revealed by using true triaxial experimental system, and the difference of main stress and displacement of confining pressure are given. The influence of plane and primary fracture on the propagation of hydraulic fracture is considered, and the stress and strain state of surrounding rock and the effect of roof control are considered. This paper expounds the principle of the proper position of the fault top line of directional fracturing near the hollow hard suspended roof, and gives the spatial-temporal relationship and the determination method of hydraulic fracturing of mining rock mass, aiming at the control requirements of fracture morphology. This paper puts forward the control method of directional hydraulic fracturing and other systems, on the basis of which a complete set of equipment for hydraulic fracturing under high pressure in coal mine is developed. According to the characteristics of different types of engineering, the expansion of main fracture of hydraulic pressure is controlled. The crack propagation of airfoil and the action of water absorption and wetting can make the roof fall in time, realize the weakening of surrounding rock, transfer of stress and induce the coal to break coal, etc. In this paper, the suspended roof at the end of the working face, the cut hole and the hard roof in the middle of the face are developed, and the hard top coal is weakened. The whole set of control techniques, such as initial gas mining in fully-mechanized caving face, impact ground pressure and large deformation of face roadway, have been popularized and applied in Datong mining area and Shendong mining area. Compared with the traditional blasting weakening roof, the whole set of technology and equipment has been applied in Datong mining area, Shendong mining area, etc. The hydraulic fracturing weakening roof has the advantages of simple management, small disturbance, high safety, small engineering quantity, wide range of action, long control distance and less than 1 / 10 of its economic cost, which is more advantageous in deep mining.
【作者单位】：中国矿业大学煤炭资源与安全开采国家重点实验室;中国矿业大学安全工程学院;
【基金】：国家优秀青年科学基金项目(51522406) 江苏省“六大人才高峰”资助(2014 ZBZZ 007)~~
【分类号】：TD327.2

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