Research On Stability Of Building Foundation Based On The Bearing Capacity Of Foundation In Mining Subsidence Areas Of Zhaogu NO.1Coal Mine

After the coal mining, the surface subsidence is caused by overlying rock, which appeared thedeformation damage. In the course of the deformation, it comes about the Settlement deformation,horizontal deformation, tilting deformation and curvature deformation, and they have an effect on thestability of building foundation in subsidence areas. During the constructing ecological mine, it takessubsidence areas as construction land in many coal mines. This not only realizes subsidence areas’governance, but also relieves the tension problems of construction land in mining areas. In order to planscientifically and use the subsidence land, we had to analyse comprehensively the deformation andevaluate the foundation stability by the action of building load on the building foundation of subsidenceareas.The paper takes subsidence areas as the engineering background, combines with its mininggeological conditions after initial mining face mining in the Zhaogu NO.1Coal Mine earth one Panel,and applies comprehensively Soil Mechanics, Probability Integration Method, Numerical simulationMethod and so on.Firstly, analyse the major influential factors of having an effect upon building foundation stabilityof subsidence areas, and they are coal seam mining thickness and depth, coal seam inclination angle,overlying rock properties, coal mining method, gof process mode, mining area layout, repeated mining,loose level thickness, load size of imposing the building foundation, and load positions of buildings insubsidence areas.Secondly, according to the theoretical calculating formula of ground bearing capacity in the soilmechanics theory, analyse the major influential factors of building ground bearing capacity insubsidence areas, and they are internal friction angle, cohesive, and foundation base buried depth,especially physical and mechanical properties of soil. Analyse the maximum damage height of the rooffall zone and fissure zone after coal mining, and calculate the foundation disturbance depth by the actionof building land, therefore put forward critical disturbance depth.If the actual disturbance depth is lessthan the critical disturbance depth, building foundation will be unstability.Thirdly, use Numerical simulation analysis method and analyse the reformation by the action ofdifferent locations of the building foundation and different load size in subsidence areas, the deformationin the inflection point area is more than it in the marginal area, and the deformation in the marginal areais more than it in the center area. Finally, analyse qualitatively physical and mechanical properties’ change of soil by land deformation and bring the changes of ground bearing capacity. Use thesubsidence and redeformation prediction model, and forecast the redeformation maximum.Combined with limit value, critical disturbance depth, ground bearing capacity and the result ofNumerical simulation Analysis of redeformation, analyse and evaluate comprehensively the stability ofbuilding foundation in subsidence areas. The stability divides into four areas that the first district isstable, the second district is general stable, the third district is unstable, the forth district is basic stable.This provides reference for the future land resource reuse in subsidence areas.