Open hole compressive strength of composite laminates and sandwichpanels: comparison between Budiansky–Fleck–Soutis model and experiments

Abstract

In this study, the compressive behaviour of carbon fibre reinforced plasticquasi-isotropic laminates and sandwich panels with carbon fibre reinforcedplastic face sheets and syntactic foam core has been investigated. Experimentallydetermined open hole strengths have been compared with theoretical predictionsobtained by applying a linear cohesive zone model. The unnotched compressivestrength has been experimentally determined, and the in-plane fracture toughnesshas been analytically predicted as input parameters of the model. Bucklingphenomena occurred on some specimens, and they have been taken into account.Evaluation of macroscopic failure modes in compression tests on unnotchedspecimens led to a better understanding on the advantages of the analyticalmodel and on the possibility of applying the model to sandwich structures.The experimental results were in good agreement with the analytical predictionby the Budiansky–Soutis–Fleck cohesive zone model, and the differencebetween theoretical and experimental open hole strengths of Syncore sandwichpanels was <9%.