Impact Of The Mountainous Terrains On The Mining Subsidence Law

Ground surface movement and deformation caused by the exploitation of coal resources has a great impact on the safety of mining coal, building and the natural environment, thus mining subsidence has always been a people’s concern.Mountain surface movement deformation caused by mining has its own characteristics, and is not as the same as the flat, the surface movement deformation degree is not only related to the geological and mining conditions, such as coal seam occurrence condition, and the effect of topography and landforms is also a factor that cannot be ignored. Now, although the research on the law of mountain surface movement and deformation caused by mining is becoming more and more increasing,and the research achievements is more and more rich, but the research on micro-landform influence on mining subsidence laws is still imperfect. Therefore, it is very important and necessary to study the movement and deformation of the landform with different characteristics in mountain area under some mining conditions.In this paper, the surface morphology has been simplified to four kinds of typical geomorphic mountains, based on the topography and landforms. On the basis of the geological structure and stratigraphic characteristics of Yangquan mining area, building five models by FLAC3D numerical simulation software, simulating the surface deformation degree of the different landscape characteristics in Yangquan mining area geological conditions, the characteristics of the ground surface movement and deformation in typical physiognomy and flat mining have been contrasted, and the surface movement observation station has been set up in71503working face of Yangmei Group for the field observation. After analyzing the measured data, comparing the measured data of experiment combined with the results of numerical simulation analysis, it is concluded that the mountains terrain and landforms of the law of mining subsidence. The main research results are as follows:1. The surface movement deformation law is related to surface inclination. When the morphology of the slope is the positive slope, the horizontal movement quantity of the slope should be greater than the ground; When the morphology of the slope is the negative slope, the horizontal movement quantity of the slope should be less than the ground; The slippage of the slope on bottom part is significant, but is small on top part; The surface subsidence quantity of the slop on top part is greater than the ground, but the surface subsidence quantity of the slop on bottom part is less than the ground.2. The surface movement and deformation is affected by the concrete form of the microrelief. Above the mined-out area, the subsidence value of the convex landform increases, and the horizontal movement value in mountain mining decreases; The mining slip of the convex landform can cause the surface subsidence; The surface subsidence value of the concave landform parts decreases, and the horizontal movement value in mountain mining increases; The mining slip of the concave landform may cause the surface upraised.3. The surface movement and deformation is the result of comprehensive action of the slippage pointing at the goaf and the slide horizontal movement pointing at the downhill of slope; the distributions of the mountain surface movement and deformation are different from the ground, mainly due to the influence of the additional slippage of the topography and landforms.4. The distribution curve forms of the mountain surface movement and deformation have no longer symmetry and similarity; The influences of the mountainous terrain on deformation are far larger than on subsidence, and the horizontal deformations are sensitive to changes in terrain; The fluctuation of the movements and deformations is obvious near the points in which the direction and gradient of the slope have changed.