Study on rational width of gateway protecting coal pillar in fully mechanized top caving mining face

In view of the occurrence condition of soft roof and floor with hard 5# coal seam in Xin-bai Colliery of Tuating Coal Field,the stress distribution and the failure characteristics in surrounding rocks of roadway were studied with respect to different pillar widths using theoretical analysis and numerical simulation.Through the general analysis and assessment on stability of the roadway system protected by the pillar with different widths,the reasonable pillar width was determined for roadway driving along gob between adjacent working surface sectors,which provides reference to the determination of reasonable position of similar roadway driving along gob.