Industrial Testing on Working Face Passing Abandoned Roadway Under Pier Column Filling

When coal mine collects coal pillars, working face must pass the abandoned roadways in coal pillars. Due to the role of advanced abutment stress, it is difficult to pass abandoned roadway for working face. Through the analysis of mechanical state changes at abandoned roadway roof with different pier column filling schemes. UDEC software is used to simulate the whole process of working face passing abandoned roadway with different filling conditions. The article analyzes subsidence and two wall deformation of abandoned roadway in the process, and working face safely passes the abandoned roadway.