Experimental validation of an algorithm for masonry vaults reinforced by the Ω-Wrap technique

Abstract

Assessment of the effects of the application of advanced materials and new technologies on traditional structures has assumed a major relevance within the ongoing debate on the preservation of historic buildings. The aim of the present paper is to discuss the validity of analytical models, by means of experimental investigations carried out on masonry arches reinforced with an innovative technology proposed by the same author and based on the use of CFRP strips, with a special configuration called an “Ω-Wrap”. A theoretical prediction of ultimate strength was derived in agreement with the occurrences observed during the experiments (masonry crushing, FRP rupture, debonding, sliding along the mortar joint). The results of the experimental trials allowed us not only to validate the proposed analytical derivations but also to evaluate the impact of these innovative reinforcement configurations on the strength of masonry arches. So a lower bound limit analysis approach was developed which can handle with the shear strength of each ideal sections given by the Mohr-Coulomb friction law (for the mortar joint) and other non linear Italian Code relations (for CFRP Ωwrap reinforcement) at a given level of normal compressive stress, resulting from the previous step. In this way the associated flow rule holds at each step for the shear failure mechanism also without dilatancy.