Bearing characteristics and rational width of the road-side infills in gob-side entry retaining at inclined coal seams
To study the bearing characteristics and rational width of the road-side filling body in gob-side entry retaining in inclined coal seams,taking the gob-side entry retaining at No.7 working face on the left of Xintie Coal Mine in Heilongjiang Province as the background,in terms of the theoretical analysis,we analyzed the dynamic impact and static pressure of gangue,analyzed their influencing factors.The numerical simulation software was also used to analyze the stress distribution and deformation characteristics of wall rocks in retaining roadways along gob with filling in different widths,present the bearing characteristics of the filling,and determine the rational width for engineering application.The results show that the dynamic impact of gangue on roadway side filling increases with the expansion of gangue weight,mining height and coal seam dip angle,and decreases with the extension of collision duration and slip length.The static pressure effect of gangue on roadway side filling increases with the increase of gangue bulk density,coal seam dip angle,mining height and working face length.The minimum width of the roadway side filling is theoretically calculated to be 1.36 m.With the increase of the width of the filling,the bearing capacity and deformation resistance of the filling increases gradually,and the'elliptical elastic core which is inclined towards the goaf is formed inside the filling.Hence,the width of the roadway side filling is determined to be 2 m.The engineering application shows that the deformation of surrounding rocks in retaining roadways along gob is small on the basis of above parameters on roadway side filling,which meets the needs of daily production.
NETL
NSTL
万方数据
