In the context of seismic risk, studying the characteristics of urban soils and of the built environment means adopting a holistic vision of the city, taking a step forward compared to the current microzonation approach. Based on this principle, CLARA WebGIS aims to collect, organize, and disseminate the available information on soils and buildings in the urban area of Matera. The geodatabase is populated with (i) 488 downloadable geological, geotechnical, and geophysical surveys; (ii) geological, geomorphological, and seismic homogeneous microzone maps; and (iii) a new Digital Surface Model. The CLARA WebGIS is the first publicly available database that reports for the whole urban area the spatial distribution of the fundamental frequencies for soils and the overlying 4043 buildings, along with probability levels of soil-building resonance. The WebGIS is aimed at a broad range of end users (local government, engineers, geologists, etc.) as a support to the implementation of seismic risk mitigation strategies in terms of urban planning, seismic retrofitting, and management of post-earthquake crises. We recommend that the database be managed by local administrators, who would also have the task of deciding on future developments and continuous updating as new data becomes available.

Civil infrastructures (i.e bridges, galleries ...) are crucial parts of the road asset and their possible degradation, with related consequences, may have great social, economical and safety impacts. On these grounds, the periodic monitoring of such infrastructures, from a static and dynamic point of view, is required for identifying possible changes in the structure properties, in order to prevent serious damages and disasters.In this study we propose an integrated geophysical approach by using non-invasive and non-destructive seismic and electromagnetic techniques with standard and low-cost sensors. It has been implemented to understand the static and dynamic properties of the Gravina bridge and its interaction with foundation soils. Gravina Bridge is a bow-string bridge located few km far from Matera (Southern Italy) and developing for 144 m along a steel-concrete deck. First, the properties of the foundation soils were studied by carrying out three high-resolution geo-electrical tomographies, one bi-dimensional seismic array and two single-station seismic noise measurements. Then, the structural characteristics of the bridge were inferred through seismic and electromagnetic sensing. The former was performed by means of recordings by accelerometers and velocimeters. The accelerometers were installed in a continuous acquisition mode, along the deck and on the top of the arch. In that way, several local and regional earthquakes were recorded and detected. The velocimeters were deployed along different seismic array configurations for on-demand ambient noise recordings, in normal traffic conditions and during vibration tests. The latter were executed by using vehicles as dynamic sources.The electromagnetic sensing was performed by using the Microwave Radar Interferometer: it was placed below the deck to measure the displacements of all the scenario illuminated by the antenna beam providing a continuous mapping of the static and dynamic displacements of the entire target.The acquired dataset was analyzed both in frequency and time-frequency domain in order to characterize the stationary and non-stationary response of the monitored bridge in terms of fundamental frequencies of vibration, equivalent viscous damping factors and modal shapes. The consistency between the results retrieved by different geophysical techniques provides therefore an importan hint about the reliability of the described approach.

In the context of seismic risk, studying the characteristics of urban soils and of the built environment means adopting a holistic vision of the city taking a step forward compared to the current microzonation approach. Based on this principle, CLARA WebGIS aims to collect, organise, and disseminate the available information on soils and buildings in the urban area of Matera. The geodatabase is populated with i) 488 downloadable geological, geotechnical, geophysical, surveys; ii) geological, geomorphological, and seismic homogeneous microzones maps and iii) a new Digital Surface Model. The CLARA WebGIS (https://smartcities-matera-clara.imaa.cnr.it/) is the first publicly available database reporting for the whole urban area the spatial distribution of the fundamental frequencies for soils and the overlying 4043 buildings, along with probability levels of soil-building resonance. The WebGIS is addressed to a broad target of end users (local government, engineers, and geologists, etc.) as a support to the implementation of seismic risk mitigation strategies in terms of urban planning, seismic retrofitting, and management of post-earthquake crises. We recommend that the database be managed by local administrators, who would also have the task of deciding on future developments and continuous updating as new data becomes available.