Daliuta 22615 Working Face Goaf Overburden Structure Characteristics And Surface Subsidence Prediction

China's coal resources in the western region is very rich,due to the simple coal storage conditions and the thickness of the characteristics of large,for the coal mechanization,high-intensity mining provides a unique condition,but due to high-intensity mining caused by serious subsidence of the local ecological damage Environment,so that the rapid deterioration of the ecological environment and affect the socio-economic sustainable development.Therefore,it is of great significance to study the surface subsidence prediction of shallow mined-out area.The paper uses the similar experiment,numerical simulation,theoretical analysis and field measurement method,The structural characteristics of overburden and the prediction of surface subsidence are carried out.The occurrence conditions of the coal seam in the mining area are characterized by buried shallow,thin bedrock and thick sandy soil.The movement and deformation of the overlying strata after coal mining are obviously different from those of the general mining area.Therefore,in view of the occurrence condition of shallow coal seam in Shendong mining area,Through the field sampling,the mechanics properties of the rock mass in the gob of the goaf are carried out,the mechanical properties of the rock mass are measured and the deformation characteristics of the rock mass are carried out to determine the relationship between the rock mass stress and the coefficient of the coefficient of shrinkage.The subsidence prediction study provides the basic parameters.Based on the mechanics parameters of the gobling rock mass,a two-dimensional physical similarity simulation model was established to analyze the overburden fracture and the overburden structure of the goaf under the excavation of the shallow coal seam.At the same time,the flash spot was arranged on the model,Data collection and analysis of overburden movement and deformation are carried out.Based on the study of the structural characteristics of the overlying strata,the dynamic analysis of the goaf with cantilever beam,cantilever beam,stress arch and old roof rock is analyzed by using the UDEC numerical simulation.And the mathematical model of the distance between the rock mass and the coal wall in the shallow goaf area is deduced.The buckling-stress relationship of the rock mass is brought into the mathematic model of the deformation of the rock mass in the shallow-buried goaf.The fracturing characteristics are divided into two parts.The surface subsidence of the goaf And predict the rationality of the forecast by field measurement.Finally,a complete method of surface subsidence prediction is established...