Crash simulations for increasing the passive safety of railway vehicles

Safety of railway vehicles is based on the railroad-specific principle of track guidance und keeping distance by signalling systems. Although the rates of accidents are low, during the recent years studies have increasingly been carried out to enhance passive safety, wich up to now has implicitly been defined by static criteria. Derived from accident statistics scenarios have been developed for future European standards on the crashworthiness layout of vehicle structures. Controlled absorption of the energy set free during a collision requires energy absorbing zone with suitable characteristics. For commonly several vehicles are coupled to a train, the energy absorption can - especially concerning a collision of two trains - profitably be distributed among the end zones of several vehicles. For investigating the behaviour of cars in a trainset the single-dimensional multi body simulation is most likely to be applied, modelling the cars as lumped masses and the crumble zones as springs with nonlinear characteristics. The behavior of the car structural areas involved in energy absorption can be determined by crash simulations using finite element models. During the design process the deformation characteristics of the crumble zones have to be optimized to make the trainset behave in the requested way.