Research On Supporting Scheme For Floor Heave Of Main Return Way And Its Application In Guanjiaya Coal Mine

It is an urgent problem to be solved for safe and high effective coal mining to control the deformation of soft rock roadway subject.Under the influence of mining and underground water,the bottom floor of the roadway is seriously depressed,which brings great hidden danger to the safety production of coal mine.Therefore,it is of great practical significance to explore the mechanism of the floor heave and the surrounding rock control theory.As the main return way of Guanjiaya coal mine is an engineering example.Using the method of theoretical analysis,field monitoring,analyzed the cause of instability of roadway floor deformation,roadway floor heave is determined by rock lithology,stress,water and other causes of compound floor heave.Using the method of theoretical calculation and engineering analogy method determining return air as loose big circle,soft rock tunnel excavation roadway floor and put forward the base anchor reinforcement scheme and anchor reinforcement scheme.Established FLAC3D Mohr-coulomb numerical model,simulation analysis was carried out on the supporting schemes,compared to the displacement and stress under different supporting conditions,the change of plastic zone characteristics,determine the scheme of anchor support in industrial test,the scheme of the field monitoring results show that the stability of roadway surrounding rock,satisfies the requirement of engineering practice.The bolt and grouting support in the main return way ensures the safety production of the mine.The support is guidance on the other coal mine soft rock roadway.And it is also a reference for the same conditions of soft rock roadway.