Reliability of different test setups and influence of mortar mixture on the fabric-reinforced cementitious matrix-to-brick bond response

The results of four different bond tests, conducted on specimens made of bricks and fabric-reinforced cementitious matrix (FRCM) composite strips, are presented in this article. The composites consisted of a basalt textile embedded in four types of inorganic matrices: a commercial product made of lime mortar and three different mortars properly prepared in the laboratory. Bond tests were carried out to highlight variations in the bond behavior of the four composites. The experimental campaign, for all the tested composites, confirmed that the debonding mechanism occurs at the textile-matrix interface with large differences, in terms of load carrying capacity, between the four typologies of FRCM composite. In particular, composites made up of a commercial matrix were demonstrated to be the best ones to fully exploit the tensile strength, whereas composites made up of cement-lime mortar showed the worst bond behavior. Furthermore, the results of the four bond tests conducted on the same type of composite were compared to evaluate the reliability of the different types of bond tests. Among the apparatus used to conduct the four bond tests, the single shear test was demonstrated to be the most effective for determining the actual bond performances of FRCM composites.