Stress analysis of longwall top-coal caving face adjacent to the gob

ABSTRACT

In longwall top-coal caving (LTCC) mining, progressive failure process of top coal is closely related to the mining-induced stress. In order to achieve failure mechanisms of the top coal, stress distribution of the LTCC face adjacent to the gob is analysed in this study with field investigation and numerical simulation. The concentration and rotation phenomenon of the principal stress are recognised. Particular emphasis is placed on rotation characteristics of the principal stress in the top coal adjacent to the gob. In addition, the influence provided by periodic rupture of the main roof on the mining-induced stress is discussed.