The paper deals with the strengthening of thin masonry vaults by means of a CRM (Composite Reinforced Mortar) strengthening technique based on Glass Fiber-Reinforced Polymer (GFRP) meshes embedded in a 30 mm thick mortar matrix, applied at the vault extrados or intrados and connected to the masonry abutments through steel bars and GFRP elements. The experimental campaign concerned quasi static cyclic tests performed on four full-scale samples, supporting their self-weight only and subjected to uniform horizontal transversal loading. The results of the tests are described in terms of crack pattern, failure mode and load-displacement graphs, referring both to the horizontal displacement monitored at the crown section and to the sliding at the spring sections. High improvements in terms of both resistance and displacement capacities emerged in respect to the plain masonry and the connection with the abutments resulted fundamental for ensuring the reinforcement effectiveness.
