Remote monitoring of a concrete bridge through InSAR and GNSS measurements

Abstract

Structural Health Monitoring (SHM) can support decision makers in structural integrity management by providing information about occurrence of damage and its evolution in time. Nevertheless, the adoption of traditional SHM systems, e.g., vibration-based SHM systems employing accelerometers, involves laborious installations and maintenance of the instrumentation (e.g., sensors, cables, acquisition systems), which is typically directly installed on the monitored structure. Recently, thanks to new Synthetic Aperture Radar missions, remote sensing provides promising methodology capable of monitoring infrastructure assets. This paper investigates the use of Multi-Temporal Interferometric Synthetic Aperture Radar (MT-InSAR) processing as a suitable tool for monitoring the structural health of bridges. The full interferometry processing chain is based on Sentinel-1 radar data and a combination of open-source routines. The feasibility of the remote monitoring strategy is assessed on a concrete bridge on which GNSS receivers are installed. To validate the methodology, MT-InSAR-derived time histories are verified against the GNSS-derived ones.