Surface damage characteristics in shallow-buried coal seam with strong disturbance mining: taking Shendong coal mine district as an example

Using field measurement and theoretical analysis studies surface discontinuous deformation and lasting time of surface movement in Shendong mining district in this paper.It describes the connotation of strong disturbance mining, and proposing in accordance to the maximum surface subsidence velocity, extent of damage and weighting intensity of mining face as a judge index.It summarizes the two strata movement types of bedrock falling with whole thick and partial destruction in Shendong mining district.It analyzes and summarizes the laws of strong disturbance of surface movement accompanied with discontinuous deformation as the main feature in Shendong mining district.Firstly, maximum surface subsidence velocity is 700 mm/d; then, discontinuous deformation is mainly composed of cracks and steps, mining cracks developed in the form of crack zone, the spacing of the main crack is the basically same as the periodic weighting interval of face, the main crack lag angle is about 79.8° in the foremost crack zone, the widest surface crack lag angle is 58.2°; finally, the number and width of crack development are closely related to soil properties, so crack width is generally less than 30 mm in aeolian sand area and is generally greater than 50 mm in the viscous surface area, the width and depth of crack are approximate linear correlation.This paper can provide a reference for mining damage, surface environmental control and mining design under similar mining conditions.