NUMERICAL INVESTIGATION ON DELAMINATION GROWTH IN COMPOSITE PANELS INCLUDING FIBRE-BRIDGING EFFECT

In this work, the delamination onset and propagation in composite panels with induced defects is numerically investigated by means of a robust numerical procedure, called SMXB-FB and implemented in ANSYS® FEM code by Ansys Parametric Design Language. The used methodology is based on the Virtual Crack Closure Technique (VCCT) and is able to avoid the time-step and mesh dependency issues of the standard VCCT based delamination growth approaches. In addition the proposed model takes into account the Fibre Bridging phenomenon by considering the real variation of the Critical Energy Release Rate associated to the Mode I failure mechanisms (peeling). A sensitivity analysis has been performed to assess the influence of the geometrical parameters on the delamination growth and the carrying load capability of a composite plate with a through-width delamination under compression in the presence of the fiber bridging phenomenon. Three different material models have been adopted: high sensitive, sensitive, and insensitive to the fiber bridging phenomenon to better point out how the fiber bridging phenomenon can delay the delamination growth and influence the compressive behaviour of the composite plate.