Delamination is one of the main failure mechanisms in bonded composite joints. Owing to a considerable spatial scatter in adhesion over the interface in such joints, initiation of a delamination zone and propagation of its front are highly random processes. The main delamination front is rather tortuous, and many small delamination spots are formed in its immediate vicinity. These processes can be additionally complicated in the case of loading types such as fatigue and/or multiple impacting. This paper deals with experimental methods of analysing delamination zones at various stages of their evolution. X-radiographs of delamination zones are digitalized and scaling analyses based on fractal and multifractal approaches are performed in order to quantify the morphology as well as the damage distribution in the immediate vicinity of delamination fronts.
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