Numerical Modelling of Bond Behavior in FRCM Composites Strengthened Curved Substrate Using Double Shooting Approach

Fiber Reinforced Cementitious Matrix (FRCM) has gained more and more popularity for building strengthening applications. However, when dealing with curved structural elements, such as arches and vaults commonly found in masonry buildings, the relevant studies remain insufficient. The challenge lies in comprehending the intricate failure mechanisms within the FRCM composite and addressing the normal stresses induced by substrate curvature along the interface. In this study, we expand our previous model, capable of delineating both internal and external composite failures, to accommodate curved scenarios. This model leverages a two-dimensional bisection procedure, incorporating the impact of substrate curvature within the interface law. Non-linear behaviors in both the mortar and substrate are effectively addressed through a recursive elastic numerical algorithm. We introduce two distinct models, one considering the upper mortar layer and the other without it. These models are validated against existing experimental data, demonstrating their performance in predicting the bond behavior of FRCM systems under shear testing.