Static expansion prefracturing roof cutting and pressure relief of fully mechanized mining face
In order to study the application effect of static expansion roof cutting and pressure releasing on fully mechanized mining face,and on the basis of determining the technical scheme of static expansion roof cutting and pressure relief of the working face,a numerical calculation model of static expansion roof cutting and pressure relief on the fully mechanized 4308 mining face of Sanyuan Coal Mine was established using FLAC3D software.The variation law of the length of initial mining hanging roof with the length of static expansion roof cutting is analyzed,and the technical scheme of pressure relief of static expansion roof cutting was determined.The results show that when the length of pre-fracturing is 0,7.5 m,15 m and 25 m,the length of hanging roof is 40 m,32 m,27 m and 26 m,respectively.The static expansion roof cutting and pressure relief technology can effectively control the hanging roof length.With the increase of the length of static expansion roof cutting and pressure relief,the hanging roof length first decreases and then remains unchanged.Considering the economic cost,the opti-mal length of static expansion roof cutting is 15 m with good results.
万方数据
维普
