【作者】 李波；

【导师】 魏建平；

【作者基本信息】 河南理工大学 ， 安全技术及工程， 2010， 硕士

【摘要】 本文针对煤厚变化大、煤体松软,透气性差且无保护层开采的煤层条件,以新安煤田义安煤矿为试验矿井,采用理论分析、现场试验考察和数值模拟等方法,开展水力冲孔卸压区域防突关键技术研究,最终达到提高抽采量、减少措施工程量、缩短措施时间和实现安全快速消除工作面突出危险的目的。水力冲孔就是在突出危险煤层中利用岩石作为安全屏障,在底板巷利用高压水射流,冲出大量煤炭和排除一定数量的瓦斯,使得煤体释放瓦斯潜能;再将钻孔闭合预抽煤层瓦斯,进一步降低煤层中的瓦斯压力和瓦斯含量,同时可以引起煤层的收缩变形、地应力下降、煤层透气性增高等变化、达到消弱直到消除突出危险的目的。为了考察水力冲孔措施的消突效果,并确定合理的有效影响半径。本文主要研究内容为:①运用损伤破坏理论将水力冲孔破煤过程划分成三个时期:裂缝产生、水楔作用、煤体破碎作用。同时分析了在不同时期内,适合哪一种煤岩强度准则。②通过在义安矿现场考察试验了水力冲孔防突措施,通过改变冲孔水压、喷嘴型号等冲孔设备,利用流量法和压力法考察出冲孔有效影响半径在6.5~8m之间。③结合RFPA数值模拟软件对在垂压一定的情况下,卸压范围内冲孔孔洞的大小与卸压范围的关系,及孔洞周围煤体应力变化、煤体位移变化、瓦斯流量变化和瓦斯压力梯度的变化规律,同时模拟了两个不同孔径的孔洞的卸压范围的变化情况。④在实施完水力冲孔措施后,在底板巷合适的位置布置钻孔,测残余瓦斯含量和瓦斯压力,测的结果为煤层瓦斯压力均0MPa,煤层瓦斯含量在3.6m3/t,与没有采取水力冲孔措施前的煤层瓦斯含量9.4m3/t和瓦斯压力0.88MPa相比,都下降到临界值以下。从而对于义安矿这种三软低透气性严重突出煤层,利用卸压增透强化抽放措施来减弱或消除工作面的突出危险性,是非常有效的。更多还原

【Abstract】 In this paper, based on the conditions of large changes in coal thickness、coal soft、poor ventilation、and no protective layer of coal mining to Xinan Yian mine for the experiment, the theoretical analysis, field test study and numerical simulation methods, to carry out unloading hydraulic flushing pressure Outburst key technology areas. The amount ultimately improve drainage, reduce the quantities of measures in order to reduce the time and the achievement of security measures to quickly remove Outburst purposes. In the high-pressure water jet Bottom Road, hydraulic flushing use the highlight risk of the of coal as a safety barrier of rock, out of a large number of coal and exclude certain amount of gas. Allows the release of coal gas potential; then closed pre-pumping coal seam gas drilling to further reduce the coal seam gas pressure and gas content, while coal seam can cause deformation, stress drop, and increase of gas permeability changes, to weaken until the purpose of eliminating outburst. In order to investigate measures to eliminate sudden hydraulic flushing effect, and to determine reasonable and effective radius of influence. This paper studies the content as follows:①the use of theory to water damage and failure process of punching broken coal is divided into three periods: crack, water wedge effect, the role of coal broken. Also analyzed at different periods, for which coal and rock strength criterion.②by Ngee Ann Mine site visit test against outburst of hydraulic punching, punching through to change water pressure, nozzle type and other punching equipment, use of flow and pressure effects were investigated by the effective radius of punching in between 6.5 ~ 8m .③combination of numerical simulation software RFPA vertical pressure in certain circumstances, relief punching holes within the scope of the relationship between size and pressure relief, and the holes around the stress of coal, coal displacement, changes in gas flow and gas variation of pressure gradient, while simulated two different holes in the pressure relief aperture range of changes.④hydraulic punching in the implementation of measures completed in the right place cloth Bottom Road.更多还原