SURFACE DISPLACEMENT MONITORING OF SUBURBAN EXPRESSWAY UNDER CONSTRUCTION BASED ON SENTINEL-1 SBAS-INSAR ANALYSIS

Abstract. The Synthetic Aperture Radar Interferometry (InSAR) technique can quickly obtain millimeter-level surface deformation in urban areas with high coherence. However, expanding the application of time series InSAR in non-urban areas is an important research focus. An improved SBAS-InSAR analysis approach is applied in this study to present the surface displacement along two expressways under construction. Taking the Kejiao and Yicheng Highway in the Shenzhen Shanwei Special Cooperation Zone as examples, the deformation along the highways under construction and the surrounding ground objects is revealed. Moreover, the time series displacements and construction conditions are combined to explain the possible mechanisms behind the different displacements of various ground objects along the expressways. The results show that the climate, environment, and construction conditions of the cooperation zone had an impact on the deformation of various ground objects along the route. Compared to traditional PS-InSAR methods, the density and accuracy of coherence points are improved, which better overcomes the spatiotemporal incoherence effects in non-urban areas.