  We demonstrate the ability of a stabilized finite element method, inspired by
the weighted Nitsche approach, to alleviate spurious traction oscillations at
interlaminar interfaces in multi-ply multi-directional composite laminates. In
contrast with the standard (penalty-like) method, the stabilized method allows
the use of arbitrarily large values of cohesive stiffness and obviates the need
for engineering approaches to estimate minimum cohesive stiffness necessary for
accurate delamination analysis. This is achieved by defining a weighted
interface traction in the stabilized method, which allows a gradual transition
from penalty-like method for soft elastic contact to Nitsche-like method for
rigid contact. We conducted several simulation studies involving constant
strain patch tests and benchmark delamination tests under mode-I, mode-II and
mixed-mode loadings. Our results show clear evidence of traction oscillations
with the standard method with structured and perturbed finite element meshes,
and that the stabilized method alleviates these oscillations, thus illustrating
its robustness.
