Study on no-impact narrow coal pillar of gob-side enery driving in western mining area

In order to solve the difficult problem of coal pillar impact control caused by the increase of mining depth in western mining area,this paper presents a design method of using coal pillar width to realize the 20～40 m of driving along goaf.This paper takes Gaojiabao Coal Mine of Binchang Mining Area as example to carry out the design principle research of the no-impact narrow coal pillar along the goaf .The stress distribution environment before and after roadway excavation was analyzed by finite element numerical simulation,and the size range of the no-impact narrow coal pillar was determined.According to the parameters of four different width coal pillars of 5，6，7，8 m,the stress state of the surrounding rock and the technical research of the coal pillar plastic compression zone are carried out,and the comprehensive comparison scheme for the safety of coal pillars，such as stress,deformation,support and disaster prevention is developed.Finally,combined with engineering analogy and theoretical analysis,the reasonable range of coal pillar parameters is determined.Considering the safety requirement of fire and waterproof,8 m coal pillar is selected,the paper studies the second time distribution law of surrounding rock stress after excavation,determines the critical parameters of the surface displacement of surrounding rock.The industrial test of 8 m coal pillar is carried out and the test results verified the rationality of the design.