Study On Reasonable Size Of 3# Coal Seam Section Narrow Coal Pillar In Changping Mine

The reasonable size of section coal pillar has been a technical problem affecting the safe and efficient production of coal mine and the recovery rate of coal resources.According to the specific conditions of reasonable size of the coal pillar caving working face section,not only for the production of mine technology,ease mining relationship and extend the mine life is of practical significance,but also to make the coal enterprises to improve safety conditions and technical and economic indicators,one of the main ways to increase production,increased profits and reduced losses.Taking Changping Coal Caving Face section of reasonable size of coal pillar as the research background,through the law of geological mechanics parameter test and failure analysis of coal pillar,the Changping Mine section coal pillar stress distribution and overlying strata breaking away from the gob side at 16 m,have set the feasibility section of small coal pillar;and then analyzes the regularity of fully mechanized caving face breaking strata section of small coal pillar,the influence of B on key block caving coal pillar mining roadway.And the key block are analyzed,and get the key block of the coal pillar force is 8.96 MPa,calculate the minimum reasonable coal pillar width value of 4.2 m using coal pillar strength theory and limit equilibrium theory,combined with the range of stress decreasing zone,can determine the range of reasonable coal pillar width;using FLAC3D the numerical simulation software to analyze the stress during the roadway excavation and stoping during different width segment coal pillar field and damage field and displacement field distribution,and ultimately determine the reasonable size of coal pillar is 6 m;the working face in Changping Mine 4309 fully mechanized on-site industrial test and displacement observation,experimental results verify the feasibility of 6 the M section of small coal pillar scheme.This study of Changping Coal Caving Face section of small pillar provides a theoretical basis for design,and provide a certain reference value to other sections of small coal pillar under similar conditions.