Abstract: The seam deposit features of Bulianta 12407 coal mining face were analyzed and the 3D geological model of the coal mining face was established by using the FLAC3D software, overlying rock movement and damage occurred by the coal mining operation is numerical simulation. The paper analyzed the displacement and stress distribution law of the strata above seam during the coal mining process and had a discussion on influence of different ratio of sand and bedrock on overlying rock movement and damage, that can forecast damage extent of the overlying rock in the mined-out area, and we can take measures to prevent to sand inrush and water inrush in the working face and protect plants on the surface.

Key words: modern coal mining, different ratio of sand and bedrock, overlying rock movement and damage, numerical simulation