Experimental investigation on masonry arches strengthened with PBO-FRCM composite

In the last two decades, Fiber Reinforced Polymer (FRP) composites were effectively used for increasing the load-carrying capacity of masonry arches and for improving their mechanical response against the most critical arch failure mechanisms. More recently, Fabric Reinforced Cementitious Matrix (FRCM) composites are appearing significantly promising for the strengthening of masonry arches, providing an alternative to the FRP composites, but only few experimental contributions are available to date. In the present paper, the structural performance of masonry arches strengthened both at intrados and at extrados by using a polybenzoxazole (PBO) fabric reinforced cementitious mortar composite was experimentally investigated. Results, in terms of load-carrying capacity, post peak behavior and failure mechanism, were compared with those determined by using a Carbon Fiber Reinforced Polymer (CFRP) composite. The present experimental study contributes to improve the knowledge of the innovative PBO-FRCM composites and it provides mechanical data useful for defining masonry strengthening design guidelines.