掘进工作面顶板水力压裂防灾技术应用研究

高瓦斯、高地应力掘进工作面顶板围岩动力现象频繁出现，严重制约了矿井安全生产。为防止煤岩动力灾害事故发生，五阳煤矿采用水力压裂技术开展掘进工作面顶板围岩卸压增透试验，以减小巷道上方应力效应、预先释放顶板瓦斯。利用瞬变电磁仪检测煤层裂隙电阻率变化以表征顶板水力压裂试验开展情况，通过对比顶板水力压裂前后工作面瓦斯浓度、煤炮响应次数及微震事件，研究顶板水力压裂技术的防灾效果。研究表明，煤层电阻率受顶板水力压裂效果影响巨大，同时压裂防灾效果明显，施工前后各项指标均有明显降低，瓦斯浓度降低40%，煤炮响应次数减小85%，微震事件减小76%。

Application research on roof hydraulic fracturing disasterprevention technology in heading face

The dynamic phenomenon of roof surrounding rock in high gassy and high stress heading face occurs frequently,which seriously restricts the safety production of the mine.In order to prevent the occurrence of coal and rock dynamic disasters,Wuyang Coal Mine adopted hydraulic fracturing technology to carry out the pressure relief and permeability enhancement test of the roof surrounding rock of the heading face,so as to reduce the stress effect above the roadway and release the roof gas in advance.At the same time,the transient electromagnetic instrument was used to detect the change of coal seam fracture resistivity to characterize the development of roof hydraulic fracturing test.The disaster prevention effect of roof hydraulic fracturing technology was studied by comparing the gas concentration of working face before and after roof hydraulic fracturing,the response times of coal cannon and microseismic events.The research showed that the coal seam resistivity is greatly affected by the hydraulic fracturing effect of the roof.At the same time,the fracturing disaster prevention effect is obvious.All indicators before and after construction are significantly reduced.The gas concentration is reduced by 40%,the response times of coal cannon is reduced by 85%,and the microseismic events are reduced by 76%.