Study on the Regularity of Surface Movement and Deformation in Long Coal Face with Large Mining Height

It is an important way to realize mine intensive production by increasing of the coal face length. During the transformation period of mining methods about thick coal seams, the character parameters of surface movement and deformation will be provided to guarantee scientifically mining of thick coal seams in Jincheng mining area. In this paper, numerical simulation, theoretical analysis and field measurement are used for studying the influence of coal face length on surface movement and deformation in the condition of large height mining. The results show that the separated strata space range extended with the increasing of coal face length and advancing distance, the surface movement and deformation become more violent, the mining influenced range also gradually expands, and the maximum surface subsidence and horizontal displacement increases gradually in form of linear relationship. In the condition of fast mining, the duration of abscission layer reduces, and the surface movement and deformation shows obviously hysteretic and zonal characteristic.