UAV photogrammetry, infrared thermography and GPR for enhancing structural and material degradation evaluation of the Roman masonry bridge of Ponte Lucano in Italy

This paper presents a case study regarding the cooperative use of non-destructive contactless diagnostic investigations as a tool to aid and assist the degradation evaluation of an iconic Roman masonry bridge: Ponte Lucano in Tivoli, Italy. Specifically, unmanned aerial photogrammetric surveys are considered to perform detailed visual inspections and obtain a geometrical 3D model; infrared thermography analyses are carried out to characterize the thermal surface map of the structure detecting anomalies related to material degradation, such as the presence of humidity; ground penetrating radar investigations are performed to improve knowledge of the bridge subsurface structure. The results of the analyses demonstrate that the integration of mentioned diagnostic tools provides information regarding the degradation state of the stones and its causes, as well as regarding the evolution of the structure from its construction up to the present configurations.