Abstract:

Aiming at the phenomenon of the law of strata behaviors being different between the below coal seam working face that the upper coal seam has been mined and common working face, the paper definition of the Loading Layer and the main Loading Layer based on the original principle about rock strata movement. The paper derives the expression of caving step length when considering the upper coal bottom failure depth. The paper analyzes the influence of the process of load-bearing layer rupturing and collapsing on the law of strata behaviors of coal seam working face. The results indicate that fracture form and motion feature of load-bearing layer has great influence on the law of strata behaviors and landmark movement, sometimes it plays a decisive role in it. Interlaminar fracture of load-bearing layer causing different strength and incidence roof weighting different strength and incidence superposes in working faces and causes the law working face weighting confusing. Rock fracture nearer to working face top has less effect on strata behaviors of working face and nearer to working face bottom. Finally, the results of the theory analysis are verified logicality and verifies the applicability widely used in many polymer melts.

Key words: short-distance coal seams group, the Loading Layer, strata behaviors, strata movement, goaf