# ADAfinder Tool Applied to EGMS Data for the Structural Health Monitoring of Urban Settlements
## 5 Conclusions  
In this paper, a methodology based on the use of the ADAfinder tool for the monitoring of the deformative condition of the constructions in urban areas was proposed. The methodology can be performed using satellite SAR data derived by every satellite constellation, processed with any existing processing techniques. In this work, EGMS data were used to demonstrate their great potential in applications regarding the structural monitoring at large scale. It is worth remembering that Sentinel-1 satellite data are cost-free, so their use could be preferable to other satellite data thinking about long-term monitoring at large scale. Nevertheless, the number of PSs over small buildings could increase by using SAR satellite data obtained by processing SAR images with higher resolution, as those derived by the COSMO-SkyMed constellation. The main output are the velocity maps along the vertical and E-W directions, which condense the most significant information about the deformation of the buildings included in the deformation-active areas. These products are very clear, simple, and useful, and could provide real support for the management of the urban areas. The potentialities of the proposed methodology have been shown out of its application over two zones of Barcelona (Spain), very distinct for the configuration and for the features of the buildings. The chosen zones include rather small groups of buildings for three reasons. First of all, for the preliminary identification of constructions potentially critical from a structural engineering point of view (e.g., affected by high values of settlements), that need a more accurate level of SHM (e.g., exploiting the PSs points belonging to the selected construction to check also the presence of differential displacements, and then integrating the knowledge with in situ monitoring techniques). The second reason is that the presented applications have been useful to test the proposed methodology at all its steps, facing different problems related to the different characteristics of the two areas. Finally, to work with small areas implies that, for instance, if there is just one building exposed to a local issue in a stable zone, the ADA tool certainly identifies this building as critical. The same building, in a greater zone with uniform high levels of displacements, could be discarded based on the velocity threshold estimated based on the total measures of the wide area. However, as the ADA tool is focused on finding active deformation on a wide area and a large dataset, coarse scale analysis that includes an entire city, e.g., all the Barcelona municipalities, could enhance the potentiality of the tool (by also checking the previous described situation). This is a larger goal that will be pursued in the next future. The procedure could be improved introducing a classification of the buildings, based on structural features (e.g., the building material, the number of floors, or the construction period), and giving a velocity threshold specific for each class. It is important to keep on working on providing tools, methodologies, or indications in general, about how to manage and use the EGMS data, which constitute a great opportunity for the large user population that could benefit from them. **Author Contributions:** Conceptualization, [PERSON] ([PERSON]), M.C., A.M. ([PERSON]) and A.P. ; formal analysis, [PERSON] ([PERSON]), M.C. and [PERSON]. ([PERSON]); methodology, [PERSON] ([PERSON]), M.C. and [PERSON]. ([PERSON]); supervision, M.C. and A.P. ; validation, [PERSON] ([PERSON]), M.C. and [PERSON]. ([PERSON]); writing--original draft, [PERSON] ([PERSON]) and [PERSON] ([PERSON]); writing--review and editing, [PERSON] ([PERSON]), M.C. and A.M. ([PERSON]). All authors have read and agreed to the published version of the manuscript. **Funding:** This research received no external funding. **Data Availability Statement:** The SAR satellite data used in this work are from the European Gound Motion Service. They are public and available.