Research on optimal layout of gateway in inclined ultra thick coal seam

In order to optimize layout of gateway in inclined ultra thick coal seam,reduce the impact of surrounding rock stress to gateway during excavation and minin g,and cut down the rate of gateway repair,the paper discussed stress distribution of goaf edge in inclined ultra thick coal seam,and calculated the stress reduction region at goaf downward of thickness 10. 3 m,inclination 39° ,depth 450 m coal seam was0 ~ 12 m with theoretical analysis and FLAC3 Dsimulation method. The paper proposed gat eway could be layout at goaf downward 7,9 or 11 m,and slected to layout gateway at goaf downward 7 m by simulated three plans. The results showed that surrounding roc k convergence amount of No. 47208 return airway at goaf downward 7 m was significantly less than No. 46407 return airway's at goaf edge 35 m during excavation and mi ning,roadway deformation amount of No. 47208 return airway was 50 percent of No.46407 return airway's after excavation steady,and average convergence amount of No. 47208 return airway was less than 30 percent of No.46407 return airway's after mining steady.