Behaviour of Existing Masonry Strengthened with a GFRP Reinforced Mortar Coating

In this paper the results of a wide experimental research programme are presented. The programme was carried out on masonry specimens strengthened with the application on both faces of the wall with a mortar coating reinforced with GFRP meshes, to demonstrate the effectiveness of this technique. The research concerns both in-plane shear (diagonal compression) and out-of-plane bending (four point bending) tests. The specimens are made with different masonry types (solid brick, rubble stones, cobblestones), various thicknesses (250-400-700 mm) and using diverse coating mortars in terms of mechanical characteristics (compressive strength 5-8-12 MPa). Moreover, the coatings were effectively linked together by using GFRP connectors (4 or 6 connectors per square meter). Thirty four diagonal compression tests were carried out to assess the in-plane shear masonry response, so to analyze the influence of the main parameters on the in-plane resistance of the wall. Some unstrengthened specimens were also tested as a reference so as to assess the increase in terms of resistance and ductility due to the application of the considered strengthening technique. Eight bending tests on full scale masonry elements were also carried out to analyze the out-of-plane flexural behavior of the wall. The results demonstrate the significant increase in bending resistance of reinforced walls compared with the unstrengthened ones.