Structural Health Monitoring of Urban Infrastructures with Time-Series InSAR Analysis

The intensive urban infrastructures including roads, subways and high-speed railways are closely related to the sustainable economic development and social stability, and also supporting spatial distribution of various functions within the city. To ensure the security and sustainable development of transportation, we evaluated the potential of high resolution time-series Interferometric Synthetic Aperture Radar (InSAR) technology in monitoring the deformations of different types of infrastructures. A spatial-temporal strategy effectively combines SAR amplitude, interferometric phase and a priori information of structures to maximize the point-like targets (PTs). High density of PTs was identified and facilitated analyzing the deformation character of individual structures. Taking Shanghai, a coastal city with severe land subsidence, as an example, the detail spatial and temporal varying patterns and possible driven force of the deformations of typical transportation infrastructures were revealed. The accuracy of our results was verified by leveling data in the same period and showed fairly consistent agreement. This study further illustrated that it is feasible to use the high resolution time-series Interferometric Synthetic Aperture Radar (InSAR) technology into the structural health monitoring and early warning of urban infrastructures.