Influence of stress distribution in coal seams of non-uniform extremely thick key stratum and disaster-causing mechanisms.

This paper analyzes the influence of the overlying extremely thick primary key stratum on the strong mine pressure hazard at the large mining face in Gaojiapu coal mine. The analysis of the distribution characteristics of the primary key stratum in the Gaojiapu coal mine reveals the bow-shaped structural characteristics of the overlying thick primary key stratum. An elastodynamic model was developed using the variational method to calculate and analyze the influence of the movement of the primary key stratum on the stress and energy of the underlying weak rock.