Tensile Behavior of Epoxy-Impregnated Carbon FRCM Exposed to High Temperatures

Externally bonded (EB) fabric-reinforced cementitious matrix (FRCM) composites, also referred to as textile reinforced concrete (TRC), are getting increasingly popular in the field of structural retrofit- ting as they combine good mechanical properties with important advantages in terms of cost effectiveness, ease of intervention, and reversibility. In addition, FRCMs have good resistance to relatively elevated temperature, also by vitue of the protecting role exerted by the inorganic matrix on the embedded textile. While polymeric impregnation of multifilament textiles maximizes the mechanical response of FRCM, it also introduces an organic element into an otherwise fully inorganic composite and, accordingly, raises some concerns in terms of high temperature vulnerability of the material. In this paper, the influence of thermal preconditioning on the tensile properties of carbon FRCM in a cementitious mortar is investigated, with special regard to the role of epoxy-impregnation of the open-mesh textile. Eight FRCM specimens are subjected to a 250-minute-long thermal preconditioning up to \(300\,^{\circ }\text {C}\) , and their mechanical behavior is assessed and compared with eight specimens in the control group. It is found that, unexpectedly, the greatest performance loss is associated with the control, as opposed to the epoxy-coated, group.