In France, one third of the people dying on the roads are killed after impacting against a hazard. In 90% of the reported cases, these accidents result from loss of control. Vehicle Restraint Systems (VRS) are specially designed to restrain an errant vehicle and to limit impact severity. Before being installed on the roadsides, these devices have to be crash-tested according to standards in order to evaluate their safety and deflexion performances. Tolerances exist on impact parameters (vehicle, vehicle mass, impact speed, impact angle, impact point …) and material’s mechanical characteristic uncertainties have an effect towards device performances and have to be taken into account during numerical simulations. Steel-wood structures present an additional numerical challenge due to wood heterogeneity and its sensibility to environment variables such as temperature and moisture content. In order to assess the effect of this variability toward safety performances, three point bending dynamic experiments on structural samples are performed and modelled. Finally, a complete model of a vehicle restraint system is built and validated according to real crash test results thanks to a parametric method. This method takes into account the variability of the parameters associated to the failure modes of the structure. Once validated the model is used to assess the effect of wood mechanical properties modifications due to environment variable variations.
