The Interferometric Use of Radar Sensors for the Urban Monitoring of Structural Vibrations and Surface Displacements

In this paper, we propose a combined use of real aperture radar (RAR) and synthetic aperture radar (SAR) sensors, within an interferometric processing chain, to provide a new methodology for monitoring urban environment and historical buildings at different temporal and spatial scales. In particular, ground-based RAR measurements are performed to estimate the vibration displacements and the natural oscillation frequencies of structures, with the aim of supporting the understanding of the building dynamic response. These measurements are then juxtaposed with ground-based and space-borne SAR data to monitor surface deformation phenomena, and hence, point out potential risks within an urban environment. In this framework, differential interferometric SAR algorithms are implemented to generate short-term (monthly) surface displacement and long-term (annual) mean surface displacement velocity maps at local (hundreds m2) and regional (tens km2) scale, respectively. The proposed methodology, developed among the activities carried out within the national project Programma Operativo Nazionale MASSIMO (Monitoraggio in Area Sismica di SIstemi MOnumentali), is tested and discussed for the ancient structure of Saint Augustine compound, located in the historical center of Cosenza (Italy) and representing a typical example of the Italian Cultural Heritage

A S.M.A.R.T. system for the seismic vulnerability mitigation of Cultural Heritages

Both assessment and mitigation of seismic vulnerability connected to cultural heritages monitoring are non-trivial issues, based on the knowledge of structural and environmental factors potential impacting the cultural heritage. A holistic approach could be suitable to provide an effective monitoring of cultural heritages within their surroundings at different spatial and temporal scales. On the one hand, the analysis about geometrical and structural properties of monuments is important to assess their state of conservation, their response to external stresses as well as anomalies related to natural and/or anthropogenic phenomena (e.g. the aging of materials, seismic stresses, vibrational modes). On the other hand, the investigation of the surrounding area is relevant to assess environmental properties and natural phenomena (e.g. landslides, earthquakes, subsidence, seismic response) as well as their related impacts on the monuments. Within such a framework, a multi-disciplinary system has been developed and here presented for the monitoring of cultural heritages for seismic vulnerability assessment and mitigation purposes*. It merges geophysical investigations and modeling, in situ measurements and multi-platforms remote sensing sensors for the non-destructive and non-invasive multi-scales monitoring of historic buildings in a seismic-prone area. In detail, the system provides: a) the long-term and the regional-scale analysis of buildings’ environment through the integration of seismogenic analysis, airborne magnetic surveys, space-borne Synthetic Aperture Radar (SAR) and multi-spectral sensors. They allow describing the sub-surface fault systems, the surface deformation processes and the land use mapping of the regional-scale area on an annual temporal span; b) the short-term and the basin-scale analysis of building’s neighborhood through geological setting and geotechnical surveys, airborne Light Detection And Radar (LiDAR) and ground-based SAR sensors. They enable assessing the site seismic effects, the built-up structural features and the surface deformation processes of the local-scale area on a monthly temporal span; c) the real- to near-real-time and building scale analysis of the heritage through proximal remotely sensing tools (e.g. terrestrial laser scanning, infrared thermal cameras and real aperture radar), combined with ambient vibration tests. They allow analyzing geometric, structural and material properties / anomalies of buildings as well as the state of conservation of structures on a real-time temporal span. The proposed approach is: Specific (it targets the cultural heritages monitoring for seismic mitigation purposes); Measurable (it provides synthetic descriptors or maps able to quantify structural and the environmental properties / anomalies / trends); Action-oriented (it provides information to plan consolidation and restoration actions for prevention activity); Relevant (it allows achieving consolidated results for cultural heritage monitoring); Time-related (it specifies when the results can be achieved). Meaningful results, obtained for the Saint Augustine Complex (XVI century) located in the historic center of the Calabrian chief town of Cosenza, are presented in terms of a web-based Geographic Information System (GIS) platform and a 3-dimensional (3D) visual software for the monitoring of environmental/urban landscapes and buildings. These tools represent the added-value products of the proposed SMART system, which allow integrating and combining multi-sensors analyses in order to support end-users involved into a cultural heritage monitoring.Copernicus MeetingsPublishedVienna | Austria | 17–22 April 20165T. Sismologia, geofisica e geologia per l'ingegneria sismic

Site Amplifications in the epicentral area of the 2016, M 6, Amatrice earthquake (Italy)

The first mainshock (Mw 6.0) of the 2016 Central Italy seismic sequence, severely struck the Amatrice village and the surrounding localities. After a few days, some Italian Institutions, coordinated by the “Center for Seismic Microzonation and its applications”, carried out several preparatory activities for seismic microzonation of the area. A temporary seismic network was installed that monitored about 50 sites in epicentral area. The network produced a huge amount of records in a wide range of magnitude up to Mw 6.5. For about half of the recording stations, detailed site characterization was undertaken, encompassing single station noise measurements and S-wave velocity profiles. The geological and geophysical data together with the collected dataset of seismic signals were exploited to investigate the site response of selected stations. Significant amplifications are found in the correspondence of several sites that experienced a high level of damage (Imcs >IX), mainly at short and intermediate periodsPublishedRoma5T. Sismologia, geofisica e geologia per l'ingegneria sismic

The Monitoring of Urban Environments and Built-Up Structures in a Seismic Area: Web-Based GIS Mapping and 3D Visualization Tools for the Assessment of the Urban Resources

In this paper, a non-invasive infrastructural system called MASSIMO is presented for the monitoring and the seismic vulnerability mitigation of cultural heritages. It integrates ground-based, airborne and space-borne remote sensing tools with geophysical and in situ surveys to provide a multi-spatial (regional, urban and building scales) and multi-temporal (longterm, short-term and near-real-time scales) monitoring of test areas and buildings. The measurements are integrated through web-based Geographic Information System (GIS) and 3-dimensional visual platforms to support decision-making stakeholders involved in urban and structural requalification planning. An application of this system is presented over the Calabria region for the town of Cosenza and a test historical complex.The present work is supported and funded by the Italian Ministry of Education, University and Research (MIUR) under the research project PON01-02710 "MASSIMO" - "Monitoraggio in Area Sismica di SIstemi MOnumentali".Published9-134T. Sismologia, geofisica e geologia per l'ingegneria sismicaN/A or not JC

The MASSIMO system for the safeguarding of historic buildings in a seismic area: operationally-oriented platforms

In this paper, the non-invasive system MASSIMO is presented for the monitoring and the seismic vulnerability mitigation of the cultural heritage. It integrates ground-based, airborne and space-borne remote sensing tools with geophysical and in situ surveys to provide the multi-spatial (regional, urban and building scales) and multi-temporal (long-term, short-term, near-real-time and real-time scales) monitoring of test areas and buildings. The measurements are integrated through web-based GIS and 3D visual platforms to support decision-making stakeholders involved in urban planning and structural requalification. An application of this system is presented over the Calabria region for the town of Cosenza and a test historical complex

Cultural Heritage and Rockfalls: Analysis of Multi-Scale Processes Nearby the <i>Lucus Angitiae</i> Archaeological Site (Central Italy)

Archaeological areas in the mountain region of central Italy can be seriously threatened by geological hazards, and efforts are required to preserve cultural heritage. The Lucus Angitiae is a pre-Roman site located along the western edge of the Fucino Basin, the largest continental depression of central Apennines. The carbonate slope overhanging the area is affected by active rockfall processes from two main rock escarpments. In this paper, rockfall assessment was pursued through a 3D kinematic modelling, performed by adopting a probabilistic approach. Specific attention was dedicated to the choice and calibration of the input data, based on field evidence and a literature review. Two different sizes of wedge-shaped rock blocks were identified on rock escarpments, and specific stability analyses were performed. Sensitivity analyses accounting for possible triggering factors, such as water pressure increase and seismic action, were also carried out, together with an investigation of the seismological characteristics of the area. The results of the numerical simulations were used to design effective countermeasures in the framework of a mitigation plan for protection of the archaeological site. Finally, clues of gravity-driven slope deformations at the slope scale were documented, framing the rockfall process in a wider geological scenario

Cultural Heritage and Rockfalls: Analysis of Multi-Scale Processes Nearby the Lucus Angitiae Archaeological Site (Central Italy)

Archaeological areas in the mountain region of central Italy can be seriously threatened by geological hazards, and efforts are required to preserve cultural heritage. The Lucus Angitiae is a pre-Roman site located along the western edge of the Fucino Basin, the largest continental depression of central Apennines. The carbonate slope overhanging the area is affected by active rockfall processes from two main rock escarpments. In this paper, rockfall assessment was pursued through a 3D kinematic modelling, performed by adopting a probabilistic approach. Specific attention was dedicated to the choice and calibration of the input data, based on field evidence and a literature review. Two different sizes of wedge-shaped rock blocks were identified on rock escarpments, and specific stability analyses were performed. Sensitivity analyses accounting for possible triggering factors, such as water pressure increase and seismic action, were also carried out, together with an investigation of the seismological characteristics of the area. The results of the numerical simulations were used to design effective countermeasures in the framework of a mitigation plan for protection of the archaeological site. Finally, clues of gravity-driven slope deformations at the slope scale were documented, framing the rockfall process in a wider geological scenario

Experimental analysis and numerical modeling of the seismic site response at Santa Maria di Collemaggio Basilica in L'Aquila

The Basilica of Santa Maria di Collemaggio is an important cultural heritage site, considered as an extraordinary example of Romanic Art in the Abruzzo Region (Italy). Erected in the second half of the XII century, it suffered numerous transformations partly due to the damages incurred as result of several earthquakes. During the April 6, 2009 L’Aquila earthquake (MW = 6.3), the Basilica was strongly dam-aged and in particular the area of the transept collapsed causing the fall of the dome. Recently the Eni Company launched the financing project “Ripartire da Collemaggio” for the restoration of this historical building. The project includes a deep geological, geotechnical and geophysical in-vestigations, still ongoing (AA.VV., 2013), that complete the infor-mation on L’Aquila subsoil already provided by numerous studies car-ried on in downtown L'Aquila (MS–AQ Working Group, 2010; Amo-roso et al., 2010; Cardarelli e Cercato, 2010; Amoroso et al., 2014; Monaco et al., 2013; Santucci de Magistris et al., 2013; Monaco et al., 2012; Milana et al., 2011). This paper illustrates the preliminary results of seismic response anal-yses carried out at Santa Maria di Collemaggio Basilica, by using EE-RA (Bardet et al., 2000), a monodimensional (1D) code, and QUAD4M (Hudson et al., 1994), a bi-dimensional (2D) software. Both programs are dedicated to model the seismic response of a site also tacking into account for non-linear soil behaviour.PublishedRome3T. Pericolosità sismica e contributo alla definizione del rischiorestricte