On the analytical determination of strain energy release rate in bonded DCB joints

A comparison of the different methods used to calculate strain energy release rate in bonded DCB joints has been made. The standard beam theory method has been shown to be in error and models with a compliant crack front have been evaluated in search of a more reliable analytical method. It is found that in fatigue testing, a beam on elastic foundation (BEF) model gives excellent results and a simple form of the BEF equation is proposed.