Finite element analyses of mode I interlaminar delamination in z-fibrereinforced composite laminates.

摘要

This paper presents a detailed numerical study of the mode I interlaminarfracture of carbon/epoxy composite laminates with z-fibre reinforcement. Thestudy was performed using a double cantilever beam configuration. A finite elementmodel was developed using thick-layered shell elements to model the compositelaminates and non-linear interface elements to simulate the through thicknessreinforcements. An existing micro-mechanical solution was employed to model thematerial behaviour of the interface element. The numerical analysis showed thatz-fibre pinning were effective in bridging delamination when damage had propagatedinto the z-fibre field; these pins provided crack closure forces that shielded thedelamination crack from the full delaminating force and moment due to appliedloads. Therefore, the z-fibre technique significantly improves the crack growthresistance and hence arrests or delays delamination extension. The numericalresults were validated against experimental data. With reference to structuralintegrity this technique can be used to design a more damage t