Integrated Use of Geomatic Methodologies for Monitoring an Instability Phenomenon

Abstract

The growing exposure of the Italian territory to hydrogeological risk, also worsened by the influence of climate change, has made the occurrence of catastrophic phenomena, such as landslides and floods, always more impactful. In this frame, geomatic methodologies can provide a crucial support in properly characterizing a potentially critical instability phenomenon, both from the spatial and kinematic view. In this work, the integrate use of geomatic methodologies, i.e., Multi-temporal Interferometric Synthetic Aperture Radar (MTInSAR) technology and structural sensors, namely biaxial tiltmeters, were employed to kinematically investigate the behavior of an urban area affected by a landslide, located in the Apulian territory. The MTInSAR analysis carried out on Sentinel-1 SAR acquisitions showed a strong non-linear behavior in the displacement-time trends, also highlighting the presence of differential motions constituting a threat for buildings. As regards the main retaining structure, currently damaged by the landslide, automatic measurements provided by the tiltmeters confirmed the presence of more active areas, as detected by the SAR observations. The outcomes of this work provided key information to the structures responsible for the management of the risk connected with the instability and allowed to address the proper design of the mitigation works.