Fully analytical model for the analysis of externally bonded composites applied to brittle supports: sensitivity analysis

Several analytical models have been proposed reducing the debonding mechanism to a bond loss event occurring in inelastic interfaces, whose mechanical properties need to be adjusted based on available experimental data. The analytical model developed by the authors and briefly recalled in this work, considers elastic FRP bonded to brittle supports by means of inelastic interfaces. In detail, the inelastic interface is described by an initial linear elastic phase (phase 1) and a decreasing exponential softening law (phase 2). This article demonstrates the reliability of the proposed model to study the adhesion performance and failure modes of FRPs applied on different brittle supports. The model is widely benchmarked using the results obtained from two laboratory investigations on flat concrete and masonry prisms reinforced with FRP composite materials and an extensive sensitivity analysis performed by varying different parameters, namely: bond length, interfacial bonding law and FRP mechanical properties. Each parameter is discussed with respect to: 1) the obtained global force-slip curves; 2) force increase; 3) post-peak response.