Tests with a Sensitive Specimen Geometry Confirm Solid Elements when the Aspect Ratio is Below Four

The 64 km/h frontal offset test is run with a deformable barrier, and the first numerical model of this barrier was made with solid elements to represent the honeycomb blocks. This required development of a special element formulation to handle the severe deformation of the solid elements together with a complex material model that could be calibrated to handle the extreme anisotropy [1]. It is herein important to notice the amount of work as well as the uncertainties with the test specimens and the test procedure to get a proper representation of the honeycomb material. It was therefore suggested to represent the barrier geometry with shell elements that were able to capture the deformation mode with local and global buckling of the honeycomb structure together with a simple model to represent the material in the 0.076 mm thick aluminium foil [2]. Effective learning based on finite element simulations requires that the numerical predictions represent the physics at a relevant level of discretisation. Here simple hand calculations following general structural rules like for example Eurocode may support the user to build a reasonable expectation of how the structure will deform. It is crucial that the numerical prediction captures the correct strain- and stress fields as input when representing the material behaviour until an eventual fracture [3]. One benefit when using a combination of element type and element mesh that predict the correct deformation mode is the simplest possible material model. The objective of this study was to presents an experimental study with a sensitive specimen geometry that confirm the element/mesh rules presented two years ago [4].2 Specimen geometry and test procedure...