This work consists of a validation of Cohesive Zone Model (CZM) laws in traction and shear, estimated by the application of the direct method, in the strength prediction of joints under a mixed-mode loading. In this context, scarf joints with different scarf angles (α) and adhesives of different ductility were tested. Pure-mode cohesive laws served as the basis for the creation of simplified triangular, trapezoidal and exponential laws that were tested for each of the adhesives. Their validation was accomplished by comparing the numerical predictions with the experimental results. The use of the direct method allowed obtaining very precise maximum load (Pm) predictions, indicating the cohesive law shape more suitable for each adhesive /geometry set. For the geometric and material conditions considered, this study has led to the conclusion that no significant Pm errors are incurred by the choice of a less appropriate law.
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