Simplified Numerical Tool for a Fast Strength Estimation of Squared Masonry Columns Reinforced with FRP Jackets

The work addresses the retrofitting of masonry columns with fiber reinforced polymers (FRP) jackets. Experimentation is still at a higher level and the study tries to enrich the set of available numerical models to estimate the capacity of squared masonry columns with a periodic arrangement. The numerical procedure assumes a strain-based incremental formulation relying on equilibrium, compatibility, and kinematic equations and precluding strenuous integration of FEs. An elastic-perfectly plastic response with a Mohr-Coulomb failure criteria has been assumed for both brick units and mortar joints. Failure of the FRP is governed by limited tensile strength and tearing (in the corners of the columns). An associated plastic flow-rule is followed. The numerical strategy has been validated with data from several experimental campaigns, with existing literature approaches and code-based formulas. A good agreement has been found and the strategy demonstrated fast (1–2 s).