Study On Grouting Reinforcement Technology Of Section Narrow Coal Pillar Of ?4309 Face In Changping Mine

In order to improve the utilization of coal resources,it has been widely used to protect roadway without coal pillar or set narrow coal pillar.However,reserve section narrow coal pillar is faced with the difficult problem of support due to the mining influence.Therefore,it is necessary to study the stability of narrow coal pillars under the condition of mining influence.According to the geological conditions and the characteristics of coal and rock deposit in Changping coal mine ? 4309,the stress distribution,plastic zone range and displacement of narrow coal pillar under the condition of mining are analyzed by FLAC3D numerical simulation.The variation characteristics of the narrow coal pillar are analyzed,and the scheme of narrow coal pillar lagging grouting reinforcement is determined.The results show that the gel time,the strength of the consolidation body and the strength of the broken coal are obtained by the test of the performance of the two-slurry slurry under the different ratio.And other performance parameters to determine the test area for the narrow coal pillar grouting the ratio of dual-slurry.Aiming at the concrete situation of narrow coal pillar in 43092 roadway,the specific parameters of coal pillar grouting were designed.It has achieved good support effect through the field industrial testing.It has a certain reference value and guiding significance for solving the similar problems in the grouting reinforcement technology of the narrow coal pillar along the roadway in the loose coal seam of Changping Mine.