Impact compression of polystyrene foam pyramids

Finite element analysis was used in the numerical assessment of the compressive impact response of a range of two- and three-dimensional truncated pyramidal polystyrene foam shapes, of the type used in protective packaging. The results were validated through the experimental impact testing of physical components. For both the truncated 2-D and 3-D pyramids, the predicted initial yield forces were within 25% of the experimental data, and the force at 50% strain within 10%, for a range of taper angles, so long as the uniaxial compressive hardening data ignored the initial stress plateau. The shape of the force–displacement response was related to the geometry of the pyramids. The observed deformation fields, on the sides of 3-D pyramids, confirmed features of the FEA predictions.