Study On The Deformation Characteristics Of Ground Residual Movement Of Steep Coal Mining

Analysis of ground movement and deformation of mining is one of the important contents in coal mining subsidence research, the research results have been widely used in geotechnical engineering and geological disasters, such as the foundation stability evaluation, collapse of mining treatment. Mining overlying strata movement and deformation and destruction is one of the important factors which cause ground movement and deformation, also the increase in coal-strata dip is the main factor causing overlying strata movement and deformation and destruction, therefore, the theoretical study of steep seam there are some difficulties, still has nor formed a relatively mature and perfect theory and methods.Basing on "Worker’s living area of GCL" project, the steeply inclined mined-out area of Dahuangshan coal mine in Xuzhou city are studied. By engineering geological survey and geotechnical investigations for the mined-out area, the ground deformation and failure mechanisms and engineering geological conditions are analyzed, the analysis includes asymmetric mobile basins, step and caving etc.. Geological-mining and rock stress mechanism of steep coal mining are described. According to the convenient application and easy calculation parameters, using the method of translating actual mining space into a "sliding space", this paper analyzes the laws of surface subsidence, the calculation parameters of "slip space" were used, a single mining working coal face with arbitrary shape was divided into several rectangular convex surfaces, and the ground subsidence caused by the expected point are added according to superposition principle to obtain a combined effect of irregular shape mining face.The contour maps of the ground settlement, residual settlement, tilt, curvature and horizontal deformation were diagramed. The deformation laws of ground movement under the condition of steep coal seam mining were analyzed, according to the codes of standards of ground deformation limits. Considering the impact of foundation engineering geological conditions, surface residual deformation values, mining methods, value divided by the thickness of the depth,"mining resurrection" and other factors on the stability of the foundation is partitioned, according to the results of the analysis evaluate foundation stability and construction suitability.