Structural consolidation with CFRP fabric of the central portal in green Cipollino marble of the Church of San Giacomo in Augusta in Rome.

Simoni Gabriela, Micheloni Michelangelo, Sollazzi Franco, Andre Valerio Canele, Mascherucci Alessandro, Porro Daniela and De Santis Massimiliano

 Abstract.

In this article we will illustrate the structural consolidation with CFRP fabric (Carbon Fiber Reinforced Polymer) carried out on the central portal of the Church of San Giacomo in Augusta in Rome in February 2025. The central portal is a monumental stone portal in Renaissance style, built in the 16th century. The mar-ble blocks of the portal are most likely from the Roman era, taken from ancient temples of this area. The structure appears to be composed of a major part of Green Cipollino Marble and for the other part of white marble. On Friday, November 1, 2024, some stone portions of the architrave of the central portal of the church acci-dentally broke off and fell onto the road below. The stone fragments that broke off and then fell to the ground shattered into two large blocks of 50 cm x 50 cm each. A detailed survey with photogrammetric technique and non-invasive diagnostic tests on the portal were performed to carry out the project. The structural consolidation involved the relocation of the detached stone elements and the consolidation of the architrave by inserting strips of carbon fiber fabric into the intrados, laid to the stone support with structural epoxy resin and anchored at the ends with carbon fiber connectors. The 600 gr/m² carbon fiber strips were arranged in a double layer on the intrados of the architrave and were then anchored at the ends with carbon fiber connectors inserted into the stone uprights of the portal to ensure effective anchor-ing. One week after the application of the CFRP, the entire lower surface, corre-sponding to the carbon fibers, was filled to imitate the Cipollino marble.