A 3D numerical model of running track performance

The present thesis work concerns the numerical simulation of the Force Reduction test, which is performed on running tracks with a specific apparatus, named Artificial Athlete Berlin, according to the standards defined by the International Association of Athletics Federations. Its goal is to investigate the shock absorption ability of a rubbery material. Aim of the work is the implementation of a three-dimensional finite element model for the prediction of the impact behaviour of structured floorings, in which the particular geometry of the cells arrays characterizing the base layers of the tracks could be introduced explicitly. Such model would enable the characterisation of a flooring impact behaviour also in the horizontal direction and the optimization of its structure, in terms of both shape and size of the base layer honeycomb pattern. Three structured running tracks were considered, differing both in terms of the cells geometry of the base layer and of the material composition. Both experimental and numerical compression tests were employed to describe the materials properties, which were then modelled with hyperelastic equations. The resulting numerical predictions in terms of impact behaviour were compared with the experimental data obtained from the FR tests performed on the same tracks, to evaluate their agreement. Finally, once the reliability of the implemented model was verified, it was employed to investigate the tracks response to slanted impacts and the influence of the variation in size and shape of the base layer cells on the shock absorption ability of the floorings.