Research On The Safety Effect Of Reconstruction To Frame Structures In Subsidence Area

In recent years,a large number of mining made the mining subsidence area became more and more,which sharply reduced the building land and the surface subsidence area construction reclamation becomes very important.For the surface subsidence area exists residual deformation,which is necessary to ensure the stability of the foundation,and to build deformation ability of the building with all the requirements on the surface.Therefore,building above the old mine area for recycling have very important theoretical meaning and engineering value.The Laohutai mining of Fushun City formed a nearly 30 square kilometers above the mined-out area of subsidence basin belongs to the ultra thick seam,which had mining for more than 100 years.Combining with the actual mine exploitation and the present situation,according to a large number of practical experience and geological data to analysis the stability of a building with frame structure of the raft foundation,determine the reconstruction spacing,and put forward some construction safety control measures on the backfill foundation with the upper structure,raft foundation and foundation interaction theory.In this article the main researches and conclusions are as follows:(1)In this article,we summarized the present situation of the research on reclamation of the subsidence area at home and abroad;Acroding to the actual mining condition of the Laohutai mining,the surface subsidence survey data and the surface subsidence of mining effect were analyzed and summarized in this paper.Also,we studyed the surface residual deformation rules of the destruction and calculate the surface construction allows the construction of time after coal mining 13 years later.(2)With the waste from mining area of coal gangue backfilling mining subsidence basin,using hierarchical framing construction of dynamic compaction method,and according the experiments to determine the subgrade bearing capacity is 220KN.The height of the upper structures influence depth and three zones damage height are 223m,less than the minimum mining depth of 670 m,and assessed the stability of backfill foundation,feasibility and determine the foundation construction of reclamation,which suitable for a six-story building.(3)It designed a six layer frame structure with raft foundation has beam plate space symmetry resistance to deformation.Select three special subsidence area position,through ANSYS numerical simulation to analyze the location of the upper structure under the condition of different engineering settlement,inclination deformation?horizontal deformation?deformation curvature and the structure internal force,to ensure the safety of the upper structure stability,minimum construction spacing and rock area.The conclusions as follow:Buildings in engineering position 1 and 3 are stable,but the project 2 can only build buildings no more than 3 follows;According to the simulation,the minimum distance between the buildings in this mining area is 1.4 times of the highest building height,and the minimum of the distance is 0.5 times of the building height.(4)For the building location which can not guarantee the security and stability of engineering should be treat,it adopted CFG pile composite foundation to coordinate the deformation of foundation and foundation,the superstructure simulate the effect in this article;In addition to mining sink area construction,we put forward some reasonable measures of resistance the deformation to the upper structure.