Compressive capacity perpendicular to grain of fully supported timber beams of Poplar - model comparison

In timber frame structures, for both residential and multi-storey purposes, timber elements are loaded perpendicular to grain. In the past, structural design code calculations were based on pre-set permissible strength values, applying empirical models with obscure background. Modern ultimate limit state structural design codes, like the Eurocode 5 (EC5) for timber structures, aim at using models that reflect "real" material behaviour. As more experimental results emerge, however, the reliability of the implemented EC5 model is questioned more and more. In the last decade a number of new models have been proposed. One is based on a fundamental principal, the so-called stress dispersion model, but the others are still empirical. This study shows the physically based stress dispersion model to be more reliable in predicting the bearing capacity of poplar for a wide range of practical design situations, than the empirical model of EC5.