基于PS-InSAR技术的昆明地铁4号线沿线地面沉降监测研究

Land Subsidence Monitoring Along the Kunming Metro Line 4 Based on PS-InSAR Technology

随着城市化进程加快,地表形变问题日益严重,逐渐威胁到城市基础设施的安全和健康发展。永久散射体合成孔径雷达干涉技术(persistent scatterer interferometric synthetic aperture radar,PS-InSAR)在监测城市基础设施地表形变领域有着独特的优势。针对地铁运营中引发的地面沉降,本研究基于30景Sentinel-1A卫星影像数据,利用PS-InSAR技术对昆明4号地铁线进行地表形变监测,并用地理加权回归对沉降结果进行插值处理,得到连续的沉降速率。研究结果表明,地铁4号线运营以后,研究区内的抬升速率由53 mm/a提升到85 mm/a;沉降速率由74 mm/a提升到137 mm/a,4号线运营后年累计沉降值约为运营前的两倍,最大累计沉降值高达171 mm,最大累计抬升量为106 mm。研究发现监测区的地表形变均与形变区的地质条件和工程施工有关。

With the acceleration of urbanization,the problem of land surface deformation is becoming more and more serious,which gradually threatens the safe and healthy development of urban infrastructure.Time-series InSAR technology has unique advantages in monitoring urban infrastructure surface deformation.Aiming at the land subsidence caused by subway construction,based on 30 Sentinel-1A satellite image data,we used PS-InSAR technology to monitor the land surface deformation of Kunming metro line 4,and interpolated the settlement results by geographical weighted regression to obtain a continuous subsidence rate.The results show that after the opening of subway line 4,the lift rate in the study area increases from 53 mm/a to 85 mm/a.The subsidence rate increases from 74 mm/a to 137 mm/a.The annual cumulative subsidence value after the opening of subway line 4 is about twice that before the opening,the maximum cumulative subsidence value is as high as 171 mm,and the maximum cumulative lift value is 106 mm.It is found that the surface deformation in the monitoring area is related to the geological conditions and engineering construction of the deformation area.