Interlaminar stresses in corrugated laminates

In axially loaded corrugated laminates consisting of more than one layer interlaminar stresses occur due to the curvature which potentially cause delamination of the laminate. Therefore, it is crucial to know how geometry and lay-up influence the interlaminar stress and hence the risk of delamination. In this paper, a parameter study is presented that studies the influence of corrugation amplitude and different lay-ups on interlaminar stresses. We considered two geometries, one consists of circular sections and the other is a sinusoidal shape. From the parameter study we can derive favorable configurations to minimize normalized interlaminar stresses. A numerical model is used to calculate the stress distribution in the cross-section of the corrugation. It considers a generalized plane strain state and uses a unit-cell approach. The model is validated with experiments in a tensile test using digital image correlation (DIC).