Experimental and numerical investigation of debonding in the composite sandwich structures with a foam-composite core under TPSB test

In the present study, the delamination between the face sheet and core in the sandwich structures with a hybrid corrugated core in the mix mode of failure under the three-point sandwich beam (TPSB) test is evaluated numerically and experimentally. The system response for different cores of the sandwich structure is compared to each other. By performing the experimental tests, the samples with different corrugated are scrutinized from various aspects, including the force–displacement diagram and the strain energy release rate diagram relative to the crack length. ABAQUS finite element software and CZM (cohesive zone modeling) method are used for numerical analysis. It is disclosed that in the studied systems, the more crack length, the more the amount of strain energy release rate, so that is generally an upwards trend in the mix-mode of failure. Additionally, it should be noted that the charts drop sharply after reaching their maximum strain energy release rate. Finally, the load–displacement curves of the specimens are extracted and compared to those of experimental data. The outcomes of the present investigation provide valuable practical tips for engineers and designers in designing composite sandwich structures.