Research on strata movement and support stability of fully mechanized sublevel caving workface with variable angle in steeply dipping seam

In order to solve the problem of the stability of support-rock system in fully mechanized sublevel caving workface with variable angle in steeply dipping seam, the fully mechanized sublevel caving mining of 120210 workface in Zaoquan coal mine was taken as engineering background. With a hybrid methodology including the plane physical simulation, theory analysis and in-situ strata control observation, the stability of support-rock system in the variable angle area was studied, and the subregional features of surrounding rock deformation and failure and support stability were analyzed. The results show that the upper region of workface is the main area of safe and efficient production, the lower region of workface is the basis for the overall stability, and the central region is the key to coordinate conversion between safe and efficient production and system stability. The control technologies of surrounding rock stability, including layout of workface readjusted to false forward slant with varible angle, subregional control of top coal caving amount and surpport loading, have been established in fully mechanized sublevel caving workface with variable angle in steeply dipping seam. © 2017, Editorial Board of Journal of CUMT. All right reserved.