Analysis Of Surface Subsidence Control Effect Of Filling Mining Based On DS-InSAR

Coal resource is an important guarantee of our energy security,however,at present,quite a few mines have been in a period of decline,the advanced mining stage is faced with the problem of coal pressure "under buildings,water bodies and railway" which are difficult to be mined by conventional methods,in addition underground mining will also cause surface subsidence,solid wastes discharge and other ecological environmental problems.Compared with caving mining,filling mining can not only improve the recovery rate of coal pressing resources "under buildings,water bodies and railways",but also effectively control the movement of overlying strata and surface,protect the safety of ground structures,but also consume part of solid waste.However,the surface subsidence control effect of different filling processes is different.Therefore,InSAR technology with all-day,all-weather,low cost and wide imaging range is selected as the surface deformation monitoring means in this thesis.The paste filling face of A coal mine,gangue filling face of B coal mine and ultra-high water material filling face of C coal mine in Jining City are taken as the research objects.Based on the monitoring results of DS-InSAR and the measured level data,the surface subsidence characteristics during mining and stoppage of different filling faces were analyzed,and the surface subsidence control effect was comprehensively evaluated.The main research work and achievements are as follows:(1)To collect and summarize the applicability of D-InSAR,SBAS-InSAR and DS-InSAR methods in different regions,and explain their principles and processing processes.Considering that all the study areas are located in non-urban areas with poor coherence,the DS-InSAR method is selected to monitor the land subsidence,and the monitoring results are compared with the measured level data.The results show that the root-mean-square error of the three DS-InSAR monitoring results is less than25 mm.(2)The DS-InSAR monitoring was carried out at different intervals in the study area.The evolution process of surface subsidence basin,the maximum cumulative settlement and subsidence velocity at different periods,and the remaining deformation duration of each filling face were analyzed by means of the DS-InSAR sequential cumulative settlement diagram and the cumulative settlement amount of monitoring points on the profile line.The mining settlement parameters such as starting distance,advance influence and boundary Angle are also calculated.The results show that filling mining can effectively reduce surface shape variables,control rock strata movement and surface subsidence.(3)The surface subsidence control effect of each filling face was evaluated based on the DS-InSAR monitoring results and the mining subsidence theory,that is,the change process of the maximum cumulative settlement point of each filling face was analyzed,the maximum surface movement deformation value and subsidence coefficient of each face were calculated,and the surface shape variables of each face mining with caving method were predicted.The influence of filling mining and caving mining on the surface villages was analyzed.The results show that the subsidence coefficients of filling 9 face in A coal mine,9302 face in B coal mine,and1312 face in C coal mine under full mining conditions are 0.09,0.17 and 0.23,respectively,which are far less than that of caving mining.In addition,compared with caving mining,the maximum surface settlement is reduced by 88%,57% and 53%,respectively.It can be seen that filling mining can effectively reduce the impact of face mining on surface buildings.Without considering other factors,the effect of filling 9 face is the best,followed by 9302 face,and 1312 face is the worst.There are 34 figures,14 tables and 96 references.