Study On The Stability Characteristics Of Small Coal Pillar In Driving Roadway Along Goaf Of Goof Cutting

As a kind of layout of coal mining roadway,roadway along the hole can effectively recover coal pillar resources,improve the recovery rate and improve the stress environment of the roadway,which is widely used in all kinds of coal mines.The research on the stability of small coal pillar and the efficient maintenance of roadway along the hole has been the focus of domestic and foreign scholars.In this paper,based on the engineering background of 2202 working face of yingpanhao coal mine,the stability characteristics of small coal pillars in gob side cutting and gob side driving are analyzed and studied,and mainly obtains the following conclusions:(1)Gob-side tunneling roadway is carried out by establishing numerical models of side roof cutting and non-roof cutting in goaf,and gob-side tunneling is carried out.the empty side of small coal pillar goaf roof of roadway roof after processing,the internal stress level significantly reduced coal pillar,the peak stress reduced by15.50%,when compared to not cut the top 15.24%The deformation of surrounding rock of gob-side roadway is reduced,the plastic zone of surrounding rock is obviously reduced,and the stability and integrity of roadway are obviously reduced.(2)Based on the limit equilibrium theory,the calculation formula of reasonable width of small coal pillar is derived.It is concluded that the reasonable width of small coal pillar is mainly affected by factors such as coal seam depth h,small coal pillar height h,small coal pillar height h,internal friction~?Angle of coal seam and the lateral pressure ~p0of goaf in the upper section.(3)Through the roof caving broken rock compression the hulking characteristics and the change rule of lateral pressure experiment,return the hulking when it gets broken rock loading curve and the lateral pressure curve,pressure curve through broken rock side macro reflects on the section of goaf caving roof and broken rock under the action of small coal pillar goaf side wall of lateral pressure variation law.(4)Focuses on analyzing the characteristics of goaf of small coal pillar stability lateral pressure,the influence of the simulation analysis of small coal pillar goaf side different lateral pressure,the deformation characteristics of roadway driving along goaf,gob side pressure has important effects on small selection reasonable width of coal pillar,the narrower the width of coal pillar,the small coal pillar under section on goaf stability when lateral pressure,the more difficult along goaf roadway maintenance.(5)Through theoretical study,numerical simulation,rock fracture and lateral pressure test research,the reasonable width of small coal pillar is finally determined to be 5m.According to the observation of mine pressure at the engineering site,after the movement of surrounding rocks along the roadway is stable,the maximum relative moving amount of the two sides is 207mm,the maximum relative moving amount of the roof and floor is 50mm,and the overall deformation amount of the roadway is small.There are only a few micro-fractures in the surrounding rock,and the roadway roof does not have large separation,so the roadway control effect is good.There are 125 pictures,10 charts and 128 references...