Plastic analysis of masonry arches reinforced with FRCM under vertical and horizontal forces

Aim of this paper is the evaluation of the increasing of the load-carrying capacity of masonry arches strengthened at intrados extrados with poliparafenilenbenzobisoxazole (PBO) fabric reinforced cementitious mortar composite. An analytical procedure is proposed, in the Limit Analysis context, considering two schemes of load: a vertical load applied at the crown of the arch and a horizontal distribution proportional to the weight. The presence of the composite material is introduced by considering a plastic behaviour of the hinges defining the virtual kinematic mechanism compatible with the Limit Analysis hypotheses. Two assumptions on these mechanisms are made: a correct position of the hinges inside the cross-section of the masonry arch or a simplified location at the intrados or at the extrados of the structure. Finally, a parametric survey is carried out in order to understand the influence of the involved parameters on the load-carrying capacity of the strengthened masonry arches.