Application Of InSAR Technology In Surface Deformation Monitoring In Nantun Mining Area

Coal plays an important role in the social and economic development of China.The surface subsidence disaster has been increasingly serious due to long-term,high-intensity and large-scale mining.In order to reduce the harm of subsidence,it is necessary to strengthen the monitoring of ground subsidence.It's also important to learn the rules of subsidence and the degree of surface damage in time,so as to use and renovate it.However,the traditional monitoring means has many defects such as high cost,large manpower consumption and limited monitoring scope,which is difficult to meet the real-time and wide monitoring demand of ground subsidence in mining area.The thesis,takes Nantun mining area as an example,applies In SAR,who has large monitoring range,continuous monitoring and high precision,to the ground subsidence monitoring in mining area.It uses stacking In SAR to solve the difficult problem of large scale deformation in the settlement center of Mining area.In order to obtain the residual settlement of the goaf in the Nan Tun mining area,the method of monitoring the residual deformation of the old Mined-out area by using SBAS-In SAR and D-InSAR,and the ground subsidence information of Nantun mining area is completed.The main achievements are as follows:1)As Stacking InSAR attaches great importance in large scale deformation monitoring,the thesis uses Stacking InSAR to monitor the two mining faces in Nantun mining area.By comparing the relationship between the difference of settlement velocity and the distance between the leveling data and the ground,Stacking In SAR results correction formula is risen up and been further verified.On the basis of which the correction formula is used to analyze the surface subsidence of 9308 and 9310 working face.The results reflect the land subsidence more accurately,and provide data support for analyzing the mining subsidence law of mining face.2)To monitor the ground subsidence in mining area,SBAs InSAR was used to test the land subsidence in Nantun mining area,so as to obtain the surface deformation information of mining area.The results show that there are 5 obvious subsidence areas,and the average subsidence speed in the middle of the image is within 30mm/a.3)To solve the problem of monitoring the residual settlement of the goaf,It analyzes the ground deformation of 6 old mined-out areas to obtain the maximum settlement velocity curves of different working faces which shows that the subsidence velocity is periodically changed,and the cumulative settlement of the central position in the goaf of 6 faces is extracted.The surface subsidence of each working face is not stopped with the stop of the working face,but the sedimentation value is increasing continuously.By analyzing the relationship between the stopping time and the settlement amount,it shows that the shorter the shutdown time,the higher the cumulative settlement in the direction of the working face.It also found that the maximum value of the settlement of the old Mined-out area is basically located in the center of the goaf,and the sinking value increases with the increase of the time.4)According to the safety monitoring of the buildings above the old Mined-out area,it uses D-inSAR to monitor the settlement of the railway above the goaf,and found that two areas with large settlement are located under the railway,and the railway lines with settlement greater than 20 mm are 746 m and 2525 m respectively.And there is a trend to increase the scope of the impact over time,which needs more attention to carry out railway maintenance work.