Marble sculptures FRP-based reinstatement and consolidation practices

FRP on historic stone artifacts still now represent innovative applications, insufficiently implemented and tested, even for structural consolidation and reinstating of marble members affected with missing parts. Under agreement with Naples' Special Office for Artistic Heritage, in 2010 Department of Materials and Production Engineering of the University of Naples designed and carried on the static reinstatement and restoration to the damaged tails of the two marble lions sculptured at the base of the monumental complex dedicated to Neapolitan Martyrs. The marble elements, differently damaged and formerly restored, have been subjected to diverse material re-adhesion and re-integration procedures, expressly draft and laboratory-tested preliminary. The recovered fragments of "Leone trafitto dalla spada"'s tail have been reassembled by inserting carbon-fiber, customer-dimensioned bars fixed by epoxy resin. The vandalized portion of "Leone dall'aspetto minaccioso"'s tail, already formerly substituted with a concrete prosthesis, has been recreated by adopting an inner expanded-polyurethane bar covered with CFRP and epoxy resin, then finished by a FRP-meshed, acrylic-resin upper coat. Thanks to an in-deep understanding of the operating procedures, basing on the fabric macroscopic survey, analytic investigations and thermography analysis, the study tested and assessed the restored fragments and prosthesis current condition, as well as the physical-chemical gripping and durability performance of the composites treatments, so deriving useful ex-post comparison about this innovative research field. (M.D.)