Distinct element analysis on coal movement law and failure mechanism during mechanized top-coal caving in steep thick seam

By using UDEC2D technique, this paper analyzed coal and rock movement laws, the deformation and failure characteristics of coal and the major principal stress in the process of top-coal caving in steep thick seam. The failure mechanism of coal and the movement trend of rock on the top-coal caving working face were discussed. The results showed agreement with the field conditions, which is of important theoretical meaning to direct the practice in the similar engineering.