STRENGTHENING OF MASONRY CROSS-VAULTS UNDER SHEAR SETTLEMENTS: COMPARISON BETWEEN DIFFERENT FRCM SYSTEMS

In this study, Finite Element (FE) models are adopted to assess the response of strengthened and unstrengthened masonry cross-vaults. Within the REVHEAL project, a full-scale (about 3.5 x 3.5 m) specimen inspired by vaults belonging to the “Palazzata” of the sanctuary “Regina Montis Regalis” (Vicoforte, Italy) has been built at Pisa Lab. of the University of Brescia, Italy. The response of the bare (i.e., unreinforced) cross-vault is predicted through the numerical simulation of full-scale tests reproducing the shear-sliding of two abutments. This loading protocol generates both shear and flexural cracks in the cross-vault and in the three boundary arches. The effectiveness of different strengthening systems, aiming at restoring the structural integrity of the cross-vault, are then investigated: (a) Fiber-Reinforced Cementitious Matrix with carbon fibers (C-FRCM); (b) Natural FRCM system with basalt fibers (B-FRCM). The modelling approach adopted to simulate the response of the FRCM systems is validated through comparison with the results of tensile tests performed by some of the authors, and other tests already available in the literature. Eventually, a numerical prediction of the shear response of the cross-vault alternatively strengthened with these systems is provided, highlighting their effectiveness in enhancing the overall lateral strength of the vault.