Stiffness Corrections for Overlaps and Gaps in Steered Composite Panel Optimization

Abstract

In this paper, a method is introduced that predicts the influence of gaps and overlaps introduced by fiber steering on the stiffness and strength of composite laminates. This method is based on the incorporation of a “density functional” which translates the effect of discrete gaps and laps into a continuous correction of the reduced stiffness matrix. It also includes a function to incorporate a fiber placement manufacturing strategy. Test configurations used to test the validity of the density functional approach show results consistent with the expected gap/overlap distributions, and also demonstrate the robustness of the manufacturing strategy function. The method is to be included in the TopSteer optimization code1 to study the influence of gaps and overlaps on optimization results.