Monitoring of a Metal Bridge Using DInSAR Data

SAR Satellite monitoring is an interesting alternative to traditional Structural Health Monitoring (SHM) techniques since it does not require the installation of sensors and enables the collection of data on a large spatial scale. The data collected by satellites are processed to obtain time histories of displacements through which phenomena such as settlements at the base of a structure can be identified and followed over time. This article provides a general overview of SAR satellite monitoring of structures and infrastructures, with a specific focus on DInSAR techniques (“Differential Interferometry Synthetic Aperture Radar”). A data processing technique is presented to analyze DInSAR displacements to gain insight into the structural behavior. The case study investigated in this paper is the Palatino bridge in Rome, Italy. The SAR satellite data are acquired by COSMO-SkyMed of the Italian Space Agency and consist of displacements calculated during an acquisition period between 2010 and 2019. SAR satellite data allows to study the structural behavior in the vertical and longitudinal (i.e., along the bridge axis) directions. The effect of temperature on the bridge behavior is investigated.