working seam
2.Taking the first coal face 1242(1) in Xieqiao coal mine as an example, the paper analyzes the regularity of strata behavior for fully mechanized working face,moving regularity of roof,performance and adaptability of hydraulic support and abutment pressure distribution of roadway.Meanwhile,the characteristic of support load during first and periodic weight of the main roof was studied.All these supply valuable experiences for extracting 11-2coal seam.
3.On the basis of similar material simulation experiment, finite element calculation and preduction practice this paper studied the laws of rock movement and abutment pressure distribution of the mining of gently-inclined coal seam group in ascending order. We obtain, through the analysis and comparisons that the features of rock movement and abutment pressure distribution in ascending mining are favourable to the balance and stability of surrounding rock of working faces, the roof control, roadways layout and their maintenance, the relation between supports and surrounding strata, etc.
4.With the theory of the systematic reliability applied, the reliable mathematical models of the extraction and conveyance system of mining section with the method of longwall mining along the single coal seam and multiple coal seams strike and that with the method of dip longwall mining are set up, and the calculating formulas of the effectiveness, the failure frequency and the average working time of these systems are also given.
