Remote Sensing Measurements for the Structural Monitoring of Historical Masonry Bridges

Advances in data processing and the availability of larger SAR datasets from various high-resolution (X-Band) satellite missions have consolidated the use of the Multi-Temporal Interferometric Synthetic Aperture Radar (MT-InSAR) technique in the near-real-time assessment of bridges and the health monitoring of transport infrastructures. This research aims to investigate the viability of a novel non-destructive health-monitoring approach based on sat-ellite remote sensing techniques for structural assessment of bridges and the prevention of damage by structural subsidence. To this purpose, commercial high-resolution TerraSAR-X (TSX) products of the German Aerospace Cen-tre (DLR) provided by the European Space Agency (ESA), were acquired and processed by MT-InSAR technique. Analyses were developed to identify and monitor the structural displacements of the historical “Ponte Sisto” masonry bridge located in Rome, Italy, crossing the Tiber River. To this extent, the historical time-series of deformations were processed by Persistent Scatterers (PSs) relevant to critical structural elements of the bridge (i.e., bridge piers and arcs). A novel data interpretation approach is proposed based on the se-lection of several PS data-points with coherent deformation trends and loca-tion on the bridge. The outcomes of this study demonstrate that multi-temporal InSAR remote sensing techniques can be applied to complement non-destructive ground-based analyses (e.g., ground-penetrating radars, laser scanners, accelerometers), paving the way for future integrated approaches in the smart monitoring of infrastructure assets.