Carbon fabric strips – Structural consolidation of the medieval bridge on Nera River

A medieval stone bridge that crosses the Nera River along a stretch of road in the hamlet of Castel San Felice, in the municipality of Anatolia di Narco in the province of Perugia, underwent consolidation works as part of a broader intervention to improve the roadway, which still remains unpaved. The bridge spans the river with a single span consisting of a low-arched vault of over 14 meters in width, accompanied by a smaller arch used for flood relief. The width of the bridge is 3.8 meters on the main arch, while the upper roadway has a transverse dimension of approximately 3 meters and a total length of about 44 meters.

ISSUES AND DAMAGE

The observed damage, although not severe, revealed a state of deterioration exacerbated by the 2016 earthquake, particularly affecting the mortar joints, which appeared washed out in many areas due to the effects of time and natural elements, compounded by the widespread presence of vegetation. The main lesions were primarily found on the intrados of the arches and at the abutment attachment on the right bank. While the smaller arch exhibited a specific lesion, the larger one showed detachment along the upstream edge following the path of the mortar joints.

INTERVENTION

The executed intervention involved the extradosal consolidation of the bridge using carbon fiber strips, supplemented by transverse micro-stitching of the side stones reinforced with carbon fiber “bows” interconnected by carbon fiber strips.