GNGTS 2022 - Atti del 40° Convegno Nazionale

GNGTS 2022 Sessione 3.2 445 Discussion and conclusions. The significancy of this study is root in the combination of valuable information and methods: a) direct inspection and oral communication with residents were transcribed for the first time; b) geological data of the study areaweremodelled in order to have a 3D reconstruction of the hill where the village of Camporotondo di Fiastrone is located; c) multiple geophysical methods with innovative non-invasive technique were combined and tested to identify underground anomalies or heterogeneities. The obtained database could be of paramount importance for the urban planning to evaluate different hazard and risk scenarios, understanding the interaction between cavities and buildings. On the other hand, the detection of unknown cavities may help in preserving the cavities as patrimonial elements, favouring the touristic development of the area. In conclusion: 1) From the investigations and considerations carried out, we can affirm that geophysics plays a vital role in the characterisation of the surface cavities present within the historic centre of Camporotondo di Fiastrone. Through a non-invasive methodology, ERT, we successfully detect both known cavities and potentially new ones. 2) Using a non-invasive non-destructive flat electrode combined with an electroconductive gel to improve the electrical contact, it was possible to overcome the problems and challenges of cavity investigations in an urban environment. 3) The cavities inside historic centres, such as the one in the present study, can represent a potential risk during seismic events. In the cavities, they also preserve a historical and cultural heritage to protect and enhance, it is therefore essential to create a database that contains all information and allows us to collect as much information as possible to understand their origin, history, and future development. 4) The presence of cavities is characterized by an increment of the resistivity in the area hosting the cavities and can be misinterpreted as a thinning of the soil/weathered levels. In the GPR section, the cavities are shown as a lack of continuity of the reflectors, but the noise and the shadow effect cause by shallower underground services makes no straightforward their interpretation. This type of study was carried out to encourage and improve the knowledge of our historic centres for a possible safety and to enhance the artistic and cultural heritage for the urban redevelopment. The proposed approach can be easily used both in other countries and in different contexts. References Argentieri, A., Di Nezza, M., Di Filippo, M., Piro, M., Rotella, G., Cecchini, F., and Margottini, S. (2018). Cavità di origine antropica e sicurezza degli edifici scolastici nella città di Roma: i casi di studio di via Asmara (Municipio II) e via Diana (Municipio V) . Geologia dell’Ambiente. Carey, A. M., Paige, G. B., Carr, B. J., and Dogan, M. (2017). Forward modelling to investigate inversion artifacts resulting from time-lapse electrical resistivity tomography during rainfall simulations. Journal of Applied Geophysics, 145, 39-49. Del Prete, S. (2008). Speleologia in Cavità Artificiali in Campania. Geologi, 25, 16-23. Lancioni, G., Bernetti, R., Quagliarini, E. and Tonti, L. (2014). Effects of underground cavities on the frequency spectrum of seismic shear waves. Advances in Civil Engineering, 2014. Park, C. S., Jeong, J. H., Park, H. W., and Kim, K. (2017). Experimental study on electrode method for electrical resistivity survey to detect cavities under road pavements. Sustainability, 9(12), 2320. Vásconez-Maza, M. D., Martínez-Pagán, P., Aktarakçi, H., García-Nieto, M. C., and Martínez-Segura, M. A. (2020). Enhancing electrical contact with a commercial polymer for electrical resistivity tomography on archaeological sites: A case study . Materials, 13(21), 5012.