Test methods for Textile Reinforced Mortar systems

Textile Reinforced Mortar (TRM) composites, also named Fabric Reinforced Cementitious Matrix (FRCM), comprise high strength textiles embedded into inorganic matrices, and have been recently developed for the repair and rehabilitation of structures. Their effectiveness and compatibility with the substrate fostered the industrial development of a wide number of strengthening systems, which have been applied to masonry and reinforced concrete structures. Nevertheless, an improved knowledge still needs to be gained on their mechanical properties (tensile and bond behaviour) and on the effect they have on the structural performance of reinforced members. Furthermore, except for the US, no standards are available for testing, qualification and design. In this paper, the main features of the tensile and bond behaviour of TRM composites are described. Recommendations for performing direct tensile tests and shear bond tests are proposed, based on the outcomes of a Round Robin Test organized by the Rilem TC 250-CSM (Composites for the Sustainable strengthening of Masonry) and Assocompositi (Italian Industry Association for Composite Materials), carried out on 26 TRM systems (made of basalt, carbon, steel, glass, PBO and aramid textiles, with cement, lime or geopolymer mortar matrices), and involving 19 European research institutions and 11 industrial partners.