ABSTRACT
Riverside alluvium areas are prone to consolidation settlements that can induce serviceability and/or structural damage to construction. Several in-situ measurements can be used to monitor soil and structural displacement. However, the use of Synthetic Aperture Radar (SAR) images has been proven to be an accurate monitoring tool for ground and structural displacements, allowing regular displacement monitoring over wide areas, with approaches such as Interferometric SAR (InSAR). The applicability of SAR images in consolidation settlement monitoring is analysed in the case study of an industrial area in the northern part of Lisbon city (Portugal). The site has been used since de 1980s and several storehouses have been built ever since. The goal of this work is to compare the in-situ measurements with long-term InSAR time series acquired by Sentinel-1 between 2018 and 2022. From 2006 and 2014, a maximum vertical displacement of ~1 m was measured with in situ techniques. The Sentinel-1 data (2018-2022) measured displacement rates between 6 and 8 mm/year. This work presents the use of the European Ground Motion Service (EGMS) time series to complement in situ measurements of the industrial area. The evolution of SAR satellites is also analysed though the comparison of the image characteristics and their influence on consolidation subsidence monitoring.
