Creep damage laws for bonded joints under pure mode II loading

Adhesively bonded joints have played an important role in several industries, mainly in automotive and aeronautics. A wide range of studies have been presented on the evaluation of the static behaviour of bonded joints, considering pure modes I and II, but also mixed-mode I + II loading. More recently, some developments have been done on the analysis of fatigue loading in this type of structural elements, introducing the importance of studying damage cohesively, along a determined period of time. As fatigue loading, creep loading can provide a significant contribution in terms of damage during the lifetime of a given bonded joint. Few studies were presented in the literature, regarding creep loading in bonded joints, so that a cohesive model capable of predicting the corresponding mechanical behaviour is needed. Twelve damage laws were postulated in this study, being used in a new cohesive zone model, predicting the creep behaviour of bonded joints under pure mode II loading. The corresponding implementation was proved, after an in-depth parametric analysis. The presented study constitutes a basis for future developments on the cohesive damage modelling of bonded joints, considering mixed-mode I + II loading scenarios.