Study On Surface Subsidence And Deformation Of Multi Goaf In Changling Coalfield,Shuangyang District,Changchun

The ground subsidence caused by the goaf left over by the historical mining of coal mine has seriously affected the normal production and life of the residents in the mining area,and also had a negative impact on the development of the local economy.At present,the surface deformation caused by coal seam goaf in Changling coalfield,Shuangyang District,Changchun has caused a large number of house cracks,serious surface deformation,damaged farmland,forests and other land resources,and seriously affected the production and life of residents of ten community of Shuangding Village.At present,it is urgent to find out the surface deformation,analyze the law of deformation and settlement,and analyze and evaluate its stability,so as to provide basis for the prevention and control of land collapse disaster.This paper takes the ten community of Shuangding Village in the Changling coalfield of Shuangyang District,Changchun City as the study area,and mainly explores the surface subsidence and deformation of the ten community of Shuangding Village.After collecting and arranging a large number of relevant documents in the mining area,comprehensively using geophysical prospecting,drilling and other means to conduct on-site investigation,the location and scope of the goaf were verified.This study is divided into three working conditions.Considering the time series mining,the surface deformation of the mining area under the real mining process is reproduced through the calculation of probability integration method and FLAC^3D software.Finally,the current situation,prediction and surface stability of the surface deformation in the study area are comprehensively analyzed,and the key hazard prevention and control zoning is carried out for the study area.The main conclusions obtained are summarized as follows:1.In this paper,the geological exploration of the study area adopts a combination of comprehensive geophysical exploration and drilling,and at the same time applies high-density electrical methods and two-dimensional seismic exploration,combined with drilling conditions,surface housing deformation and previous mine data to verify the goaf.The location and scope of the coal mine,and the subsidence area is caused by the ground subsidence formed by the goaf of the coal mine.Ground investigation found that many houses had surface deformation,among which the signs of deformation in the east side of the ten community of Shuangding Village were particularly prominent.At the same time,a comprehensive analysis of site specifications and real-world conditions determines the"three zones"height of the coal seam hoop in the study area.The height of the cave area is between 10 m and 12m,the fault area is between 35m and 45m and the bend area is between 140m and 180m.2.In this paper,the probability integration method and FLAC^3D software are used to calculate the surface subsidence deformation.Based on the timing of mining in the mining area,three different working conditions are designed to reproduce the real mining process in the mining area.Scope and rules of influence.The influence of surface deformation of the mining area on the study area gradually increases with the goaf of the coal seam,and the damage to the buildings in the area near the western boundary of the mining area is the most serious,which is mainly caused by the No.1goaf.The overall surface deformation of the study area is serious.The center of No.1mining area has the largest amount of subsidence,and the deformation is the most obvious near the boundaries of each goaf.Surface deformation is weak.The mining of the mining area has led to prominent surface deformation in the residential area in the east of ten community of Shuangding Village,serious house cracking and weak surface deformation in the residential area in the west.3.This paper compares the current and remaining surface deformation values in the study area calculated by probability integration and numerical simulation,summarizes the current situation of surface deformation,and predicts future surface deformation.According to the above-mentioned prediction results of surface deformation,combined with the relevant specifications of goaf stability evaluation,it is obtained that the maximum residual subsidence of the entire study area is within the unstable range,and the maximum residual deformation of other parameters is within the basic stable range.According to the comprehensive judgment,the study area as a whole is in a basically stable state.Then,combined with the current situation and prediction of surface deformation,a comprehensive evaluation of the risk of ground collapse in the study area is carried out.The high-risk areas are the residential area in the east of Ten Community of Shuangding Village,mining area 1 and mining area 5,with an area of 12.7hm~2.The evaluation results can provide a basis for the prevention and control of ground collapse and related disasters and the rational utilization in the follow-up study area.