The influence of mode II fracture on concrete strengthened with CFRP

The behaviour of concrete externally strengthened by sheets of carbon fibre reinforced polymer (CFRP) is analysed using the finite element method. For this purpose, a discrete crack approach based on non-linear fracture mechanics is adopted. The bond between concrete and CFRP is modelled by means of interface elements. The material properties that characterize the interface, namely the cohesion and the fracture energy in mode II, are obtained from a parametric study performed with the objective of approximating the experimental results obtained from a set of shear tests. Based on the interpretation of the results of numerical simulations of bond tests, this work aims at contributing for a better understanding, in qualitative and quantitative terms, of mode II fracture in concrete and its influence on the behaviour of the interface concrete–CFRP.