Study On The Sorting Of Influencing Factors Of Surface Movement And Deformation In Repeated Mining

In the process of coal mining, the probability of repeated mining is very high, compared with the initial mining, repeated mining damage to the surface is stronger, and there are many factors that can affect the results of repeated mining. At present, the research on the law of the surface subsidence of the repeated mining is not comprehensive,systematic and in-depth. In particular, there is a lack of research on the main controlling factors of the maximum subsidence value of the repeated mining.Because many factors can affect the results of repeated mining,through the analysis of coal seam spacing, decided to choose the thickness of bedrock and loose layer thickness as the research object,based on the three factors of the dynamic effect of repeated mining subsidence basin, and the factors of sinking the maximum main influence factors.Because of the surface subsidence of rock belongs to large deformation research, and software FLAC3D has great advantages in solving large deformation problems, has been widely used at home and abroad, get a lot of valuable practical results, to solve the large deformation problem provides a lot of valuable advice, so decided to use the software as the main research method of this paper. The simulation software based on FLAC3D, a total of 44 established the simulation model to study the various factors on the impact of the final subsidence basin and maximum subsidence, of which there are 42 models of two coal seam repeated mining, 1 model three coal repeated mining, 1 heavy mining model to simulate the transverse dynamic mapping of. Data.Using Origin software, the surface change curve of surface curves compared to 11 groups of two coal seam repeated and the other two models,then the orthogonal test method, the influence degree of three factors on the maximum subsidence value of repeated mining is sorted,the main control factors and the three factors influence sequence, degree of influence of three factors on the maximum value of surface subsidence: Bedrock thickness>Loose layer thickness> Seam spacing.Based on the results of the actual surface observation, it is found that the surface deformation law of the mining face under the condition of thick loose layer and deep well mining has the specificity.