## 4 Discussion  
The DInSAR displacement time series are clearly relevant to a defined time period, which is generally a small portion of the entire lifetime of a construction. At the end of the observation interval, the cumulative displacements can be estimated, and ground settlement profiles referred to the sides of the building under investigation can be created. Classical literature indications could be used to qualitatively evaluate the expected damage caused by such detected displacements. Nevertheless, it is worth highlighting that the latter are related only to the abovementioned satellite data observation period. Then, a real correlation between the expected and the observed damages could be truthful only for structures for which the satellite radar imaging has started at time \"zero\" of the building construction. For the purposes of this work, the main importance is given to the displacements' trend, i.e., the mean velocity in the investigated time interval. The study of the deformation velocity trends can be pursued at wide area or local scale. The trend analysis can support the interpretation of the deformation evolution, giving qualitative information about the movement patterns, aimed at the identification of critical areas or buildings in critical situations, in terms of stability, as illustrated in Section 3.3. The critical areas could be identified in a widely built environment by automating the steps of the proposed methodology. This could concern two aspects: from one side, a qualitative idea of the extension and entity of possible ongoing phenomena in the area could be retrieved; on the other side, the structures exposed to the phenomena themselves could be spatially bounded and posed under attention. The definition of the conditions that make a building defined as critical can be related to several considerations correlated to many factors of an investigated zone (e.g., geology of the area, ongoing deformation phenomena in the entire area, widespread structural typologies, average construction age of the buildings, etc.). However, exploiting the complete pattern of the deformation velocity trends of all the buildings in the monitored area, differential \"attention\" thresholds could be imposed regarding: (i) a building showing velocity values greater than those of the buildings around; (ii) a change in the velocity trends of many parts of a building over the observation period; (iii) building sides affected by differential displacements. Then, once the most exposed buildings are identified, further and more in-depth investigations should be performed. In particular, the satellite DInSAR measurements could be used to perform a structural monitoring at the detail scale, distinguishing the mean velocity values of points at different heights, and obtaining the ground displacement profiles under the building sides or at different heights (e.g., at roof height). Classical literature indications could be used to qualitatively define the expected damage which such detected displacements may cause/have caused [2]. Moreover, these displacement profiles can be applied at the ground level of the selected construction in a numerical model. Then, a structural analysis can be conducted to predict the resulting behavior and to evaluate the damage level in the single members at a local level and in the overall building at a global level, according to the selected code requirements. Finally, in this phase, it is suggested to combine on-site information (traditional measurements, such as GPS, topographic levelling tools, crack meter instrumentation, strain gauges, multi-sensor nodes, and geometrical and structural relief of the buildings) with DInSAR measurements. Some considerations can be done on the different approaches that could be used to elaborate the information derived from the PSs.