Experimental measurements and numerical modelling of bond between GFRP bars and concrete

The paper focuses on the numerical simulation of the bond between GFRP bar and concrete under static loading. Experimental eccentric pull-out tests were considered for the assessment, accounting for the influence of low concrete cover as in real structural components. 3D non-linear finite element (FE) model was adopted and validated considering the bond shear stress vs. slip behaviour and the damage patterns observed experimentally. The bond interface properties were simulated using cohesive elements by adopting the bond damage evolution approach, which consisted of two damage evolution laws: the exponential softening branch and secant modulus-based model. Bond damage models predict damage parameter evolutions close to each other and were both used for the 3D numerical simulation of the complete bonding behaviour.