摘要:The study presented constitutes the next step of authors’ investigations on the concrete composite T-shaped beams. The comparison of the failure modes and crack patterns of numerical models and beams tested was performed previously. In this paper, analyses concentrate on determination the proper values of cohesive surface parameters ensuring the high conformity of deformation and strains of the numerical model to the experimental results. In the particular series of beams the interfaces between concrete parts are varied as follows: reinforced joint with normal and tangential interactions only (BZ/S2/A), non-reinforced joint with adhesion (BZ/P), and reinforced joint with adhesion (BZ/P+S). Material properties used in numerical model are based on obtained in the laboratory ones. Furthermore, the ‘traction–separation’ law in the ABAQUS software defining the cohesion surface is used and analysis of the cohesive parameters response to interface roughness is carried out. The results show a strong dependence between the cohesion surface parameters and the response of the composite beam. A very good convergence of the numerical model with the experimental results in terms of ‘force-displacement’ relationship is achieved. Finally the parameters defined in the ABAQUS are determined, which have a key impact on the beams response.