Strata behavior regularity of 1.0 m very contiguous seams combined mining

Abstract：According to the condition of 1.0 m very contiguous seams combined mining at Yangyi Coal Mine,the range of stable-pressure and reduced-pressure which formed in the upper coal seam goaf were analysed through the theory of strata movement and conventional alternate distance theory,and it was pointed out that the lower working face can only be located in stable-pressure range and the reasonable alternate distance range in advancing direction was 21~26 m in condition of 1.0 m very contiguous seams combined mining.The research finds that overburden strata of lower working face in stable-pressure forms the double structure roof.In-site strata pressure observation results indicate that in the reasonable alternate distance range working,in advancing direction it shoud exist 2~3 m approximate rock stress safety distance between residual bearing pressure in goaf of the upper face and advance bearing pressure in front of the lower face,which can avoid the upper and lower high stress area overlying and ensure the lower face working in stable-pressure range.Alternate distance of 20~25 m on site implementation approaches to the theoretical analysis result.Through the successful implementation of 1.0 m very contiguous seams combined mining at Yangyi Coal Mine,it provides reliable strata pressure data and mining experience for other similar condition coal seam mining in the theory and technology.