Experimental and numerical investigation of core splicing configurations in an advanced composite sandwich structural system

Abstract

In this study, an investigation is presented on the effects of the honeycomb core splice gaps on the performance of advanced composite sandwich structures consisting of aluminum honeycomb core and carbon-fiber/epoxy facesheets. The experimental and numerical investigation explores the effects of core thickness, facesheet thickness, splice gap width, and the presence of core splice adhesive on the structural response of the composite sandwich structure. The specimens fabricated with the splices exposed to primarily bending and shear to understand further how the core splice interacts with the overall structural response under such loading conditions. In addition, 3D finite element models investigated the failure modes in the specimens by examining the strain fields for core-spliced sections of the sandwich structure under the experimentally observed loading conditions. Various failure modes are observed in the experiments ranging from core shear failure, facesheet debonding, or fracture depending on the location of the core splice, core, and the facesheet properties. The results illustrate the importance of proper detailing and analysis of core splices in composite structures made from sandwich designs.