Application of deciding the volue of coal seam roof strata thinkness in calculating sand content rate

Abstract：Sand content rate of coal seam roof is one of the most important factors which influences the gas content in coal seam.By using the method of correlation analysis and pregressive approximation, the correct coal seam roof thinkness was decided.A new expressed method of sand content rate, that is influence coefficient of coal seam roof strata thinkness was put forward.The sand content rate was calculated correctly, and method can be used in other coal mines.

Keyword：coal seam;stratified roof;strata;thinkness;sand content rate;