FRP strengthening -- Shear mechanism of brick masonry vaults

Strengthening of masonry brick arches and vaults with FRP laminates can contribute significantly in the improvement of their structural capacity at limit state, by activating local mechanisms both at material and interface levels. To calibrate interpretative models of the mechanical behaviour of strengthened structures, experimental procedures able to characterize the main parameters involved in the limit mechanisms are in need. In particular, for extrados applications, to counteract the possible brittle detachment during sliding at brick-mortar joints close to the springers, the contribute of the reinforcement should be taken into account. In the paper, an experimental procedure able to characterize the main parameters involved in the mechanism is proposed, and the main preliminary results are presented and discussed. A specific experimental tool has been set up, able to reproduce the local effect of strengthening. Parametric analysis of results allowed to point out that thin masonry vaults are particularly sensitive to the presence of FRP reinforcement.