Estimating crack tip position in adhesively bonded joints subjected to mode II quasi‐static loading

This study aimed at estimating crack tip position in adhesive bonded joints under mode II quasi-static loading using experimental and numerical approaches. Experimental techniques were utilized and compared, including optical backscatter reflectometry, visual testing, and a novel strategy based on digital image correlation. Additionally, a finite element analysis was employed to identify the numerical crack tip position and the extent of damage within the bondline. This analysis revealed that a significant portion of the crack propagation region in the adhesive is occupied by the fracture process zone. Moreover, optical backscatter reflectometry shows the potential to detect this process zone within the adhesive that the other methods may not detect. This capability is particularly beneficial for detecting damage at early stages.OBR and DIC were used for crack initiation and propagation in ENF joint under mode II.OBR back-face strain demonstrated its ability to detect potential early-stage damage.Trapezoidal TSL outperformed bi-linear TSL in FE crack propagation modeling.A significant portion of crack propagation region was occupied by FPZ in adhesive.