下保护层开采覆岩卸压及瓦斯运移规律  

Gas Delivery Law and Pressure-relief of Below Protected Seam Mining Under Medium Distance

作　　者：杨东 YANG Dong(Shenyang Research Institute, China Coal Technology ＆ Engineering Group Corp Shenyang 110016)

机构地区：[1]煤科集团沈阳研究院有限公司,沈阳110016 [2]煤矿安全技术国家重点实验室,辽宁抚顺113122

出　　处：《工业安全与环保》2017年第9期48-51,共4页Industrial Safety and Environmental Protection

基　　金：国家自然科学基金面上项目(51274088);国家自然科学基金青年科学基金(50804013)

摘　　要：为了研究中远距离下保护层开采覆岩卸压及瓦斯运移规律,以寺河矿和海天煤业为试验矿井,采用FLAC3D对开采覆岩卸压特征进行分析,采用COMSOL对开采被保护层瓦斯运移规律进行研究,并进行了现场实测验证。研究结果表明,保护层开采后,覆岩应力呈分区式分布,随着距煤层距离的增加,应力集中系数和卸压程度逐渐减少;保护层开采后,3#煤层应力降到最小值3.4 MPa,降幅达到57.8%;以膨胀变形量0.3%作为临界指标,被保护层的走向和倾向卸压角分别是59°,62°;保护层开采后,瓦斯质量浓度由7.82~9.75m^3/t降到4.12~4.36 m^3/t,瓦斯压力由0.37~0.46 MPa降到0.22~0.26 MPa,透气性系数增加了500多倍,被保护层产生的次生裂隙对于瓦斯解析具有促进作用,大大提高了煤体透气性。In order to research gas delivery law and pressure - relief of below protected seam mining under medium distance, taking Sihe Coal Mine and Haitian Coal Company as the experimental mine, characteristic of pressure - relief was analyzed through FLAC3 D, by using COMSOL, the gas delivery law was researched and at the same time, the field test verification was carried out. The results showed that：after the mining, overburden stress showed division -type distribution and with the increase of distance to coal seam, the stress concentration factor and degree of pressure - re- lief decreased. After the mining,the stress decreased to minimum 3.4 MPa,reducing rate reaching 57.8%. Taking swelling deformation 3%0 as critical index, the pressure relief angle of direction and tendency were 59°and 62°respectively. After the mining,the gas bearing capacity dropped from 7.82-9.75 m^3/t to 4.12-4.36 m3/t, gas pressure dropped from 0.37-0.46 MPa to 0.22-0.26 MPa, the permeability coefficient increased more than 500 times. After the mining,the secondary cracks produced by the protected layer had a promoting effect on the gas analysis and the permeability of coal was greatly improved.

关 键 词：煤矿安全 中远距离 FLAC3D COMSOL 下保护层 

分 类 号：TD31[矿业工程—矿井建设] TD712