Experimental and Numerical Investigations of Perforated FRP-Laminates
This work shows experimental and numerical investigations of perforated laminates. Perforated laminates are applied, e.g., as face sheets in sandwich compounds in the casing of aircraft turbine engines, where the effective strength and stiffness of the perforated laminate is of interest. The experimental results include the determination of critical gage lengths, acoustic emission measurements, comparison of perforated and non-perforated carbon fiber reinforced woven fabric laminates. The numerical studies show a finite element based two-scale analysis method to study problems related to the mechanical behavior of perforated laminates. Local stiffness and strength analyses are performed a 2D and 3D unit cell models including different failure models (Tsai-Wu, Puck, maximum stress, delamination) as well as the free edge effect. Effective stiffness and strength results (failure envelopes) are used for structural analysis, which does not need to account explicitly for the perforations, neither in the finite element discretization
nor in the evaluation of stress fields.