Research On The Safety Effect Of Residual Deformation To Reclaimed Buildings In Old Goaf Area

With the exploitation of mineral resources,there are more and more surface subsidence areas.Therefore,it is urgent to carry out comprehensive management and utilization of subsidence areas.From the perspective of economic input and output ratio,it is very reasonable to rebuild anti-deformation structure in the goaf.However,whether the subsidence area is suitable for engineering construction,the key factors are the stability of the foundation and the size of the residual deformation of the goaf.Therefore,the study on the effect of residual deformation on the safety of the reclaimed buildings above the old goaf has very important practical significance and reference value for the safe reutilization of the old goaf.In this paper,the mining of tigers is taken as an example to predict the residual deformation of the surface.And a systematic study of the possibility of building new buildings in the old subsidence area is carried out.The contents of this study are as follows:(1)According to the actual mining conditions in the tiger mining area and combined with surface subsidence survey data,the surface deformation law and the surface deformation characteristics of the formed goaf have been simulated and analyzed by FLAC3D,and the size of the surface residual deformation is studied systematically,and the time for the construction of the surface building after the coal mine opening is analyzed and calculated.(2)The waste coal gangue is used to backfill the old goaf,the loess cover the surface of the old goaf,and the bearing capacity of the backfill foundation of gangue is calculated by the static load method.According to the influence depth of the additional load of the building structure and the height of the three-zone damage,the stability of the backfill foundation is evaluated.And then the feasibility of the construction of the surface in the old goaf area is analyzed.(3)According to the surface deformation characteristics,these paper selects four different deformation characteristics of the regional location for engineering construction.In this case,a ten-story frame-shear wall structure is designed and a beam-slab foundation is used.The deformation characteristics of the building structure under different engineering location conditions are analyzed by ANSYS numerical simulation analysis.According to the evaluation standard of foundation stability,the safety of building structure is ensured.The optimum thickness of the beam plate raft foundation is simulated by the study of the superstructure foundation foundation joint action.(4)The curvature of the surface is used to simulate the residual deformation under different conditions,and the force deformation characteristics of the building structure are analyzed.The calculation results show that the residual deformation has great influence on the safety of the building structure and must be considered.The use of geosynthetic material reinforced bedding to treat the foundation soil can greatly improve the safety and stability of the building structure,and it is of great significance to improve the utilization limit of the weak foundation in the goaf.