Study Of Control Function Of Geological Structures On Coal-mining-induced Subsidence

In order to perfect the theoretical system of "tectonic control of hazard", this thesis researches the control function of stratum inclination of monoclinic structure, fold shape and angle between two limbs of fold, normal fault direction of dip and fault inclination, forms of faults combination over coal-mining-induced subsidence by means of theoretical analysis and numerical testing. The research is based on the geological condition and practical mining in typical coal mining areas and the production already exist. The flowing principal conclusions are acquired.(1) Under the mining of the same intensity, character of coal-mining-induced subsidence is different because of different stratum obliquity, tensile stress of the central section of roof of goaf in horizontal coal seam is obvious centralized. Shape of the surface destruction is symmetrical subsidence basin. When gently inclined and middle inclined coal seam is mined, tensile stress relative centralizes at the top mountains direction of goaf, compressed stress relative centralizes at the descends mountain direction, the maximum subsidence of ground surface excursion to mountain down, the surface destruction shape is asymmetrical subsidence basin. When steeply-inclined coal seam is mined, coal-mining-induced subsidence mostly occurs in the roof. When scope of goaf advances more deeply, unmined coal above goaf and above roof of goaf easily collapses and glide along the stratum, subsidence shape along tend towards of coal seam is half pit like graben on the surface.(2) Coal-mining-induced subsidence is relatively weaker because the anticline likes arch bridge, which has stronger ability to resist the surface deformation; Syncline structure and anticlinal warp direction are just right opposite, syncline can cause the deformation and fall of roof above goaf more easily because the remaining structure tensility overlaps with the tensility caused by mining at the transition extremity. Regarding the mining subsidence influence scope, the anticline is bigger than the lever, the syncline is the smallest. There is a...