MODE-I FRACTURE LOAD PREDICTIONS OF ADHESIVE T-JOINTS

This paper presents fracture data and a finite element analysis for ad hesive T-joints, It is shown that fracture loads of T-joints, bonded w ith two different structural epoxies and subjected to either tensile l oading or three-point bending, can be predicted using a fracture mecha nics approach. Fracture loads were predicted by calculating the applie d energy release rate, G, using finite element methods, and comparing that with a critical value, G(C), determined experimentally using doub le-cantilever-beam specimens. By recording the failure sequence of the bondline with a video camera attached to a microscope, it was seen th at subcritical crack propagation took place prior to final fracture of the bondline. Accounting for the observed subcritical crack propagati on in the finite element analysis gave a good agreement between the ac tual and the calculated fracture loads.