Research on prevention and control technology of ore pressure of over concentrated coal pillar in lower coal seam of Cuncaota No.2 Coal Mine
In order to solve the problem that the shallow buried coal seam working face is easy to cause strong dynamic ground pressure disasters when passing through the concentrated coal pillars left over by the overlying goaf,taking the No.31109 working face of Cuncao-ta No.2 Coal Mine as the research background,the characteristics of stress and ore pressure behavior when the working face passes through the concentrated coal pillars were studied by means of theoretical analysis,numerical simulation and field tests.The results showed that when No.31109 working face passed through the concentrated coal pillars left over by the overlying goaf,its roof and the roof of the goaf of this working face were easily broken and collapsed at the same time after the instability of the coal pillars.After taking measures such as reinforcement and supporting of lower coal seam mining roadway and hydraulic fracturing of overlying coal pillars,the maximum displacement of the roof and floor of the mining roadway of No.31109 working face was 193 mm,and the maximum displace-ment of the two sides was 150 mm.The working condition of the support of the working face was good,ensuring that the working face of 31 coal seam can pass through the centralized coal pillars safely.
万方数据
维普
