A zero-thickness interface model for simulating the bond behaviour of FRP-strips glued on concrete

The present paper deals with the bond behaviour of Fiber Reinforced Polymer (FRP) laminates glued to concrete substrates. It formulates a numerical approach completely conceived within the general framework of fracture mechanics which investigates the influence of different choices of the parameters describing the post-elastic process of fracture propagation. This aspect is usually neglected and the theoretical models adopted for describing bond behaviour of FRP-to-concrete adhesive joints are generally based on assuming "a priori" the analytical expression of the interface bond-slip law. Unveiling the relationships between the above mentioned fracture parameters and the resulting bond-slip interface law is the key purpose of this paper. The proposed applications point out also the differences in terms of bond behaviour of FRP-concrete joints resulting by different possible assumptions of those fracture parameters.