A Simplified Analytical Interface Model for FRCM-Strengthened Masonry

The current study proposes an analytical framework to describe the debonding behaviour of Fibre Reinforced Cementitious Matrix (FRCM)-reinforced flat masonry elements under direct shear tests. In particular, a sawtooth shear stress–slip law, which was first developed and validated for SRG systems in the shear test study in [1], is now adjusted for use with a PBO-FRCM system. Based on recent experimental investigations in [2], the shear behaviour of such systems applied to flat masonry pillars is examined. The experimental data is used to assess the performance of the sawtooth model. The approach captures key interface behaviours such as residual strength and pseudo-linear hardening and is suitable for direct use in commercial finite element (FE) software without custom coding. The results show good agreement with the experimental findings, validating the applicability of the sawtooth model to FRCM systems.