Validation Simulation of New Railway Rolling Stock Using the Finite Element Method

Bombardier Transportation is the largest manufacturer of rail vehicles in the world. The current product portfolio includes a wide variety of vehicles from low speed ‘people movers’ through to high speed inter-city trains. Bombardier offers products in every sector of the passenger rail equipment market and therefore is required to meet a number of national and international crash safety requirements. These requirements range from simple static collapse loadcases to full collision events with other rail vehicles and obstacles. As part of the validation procedure for new designs, finite element (FE) models are produced to simulate new vehicle crash performance against targets set by these requirements. The simulation of bolted and welded aluminium structures is particularly important for the Carbodies part of the business, since recent ‘real life’ crash cases have shown bolt failure and weld ‘unzipping’ as critical collapse modes for extruded aluminium carbody designs. The current technique used for modeling welded aluminium sections and particularly the heat affected zone (HAZ) is presented. Bolt failure modeling within large structures is also addressed and results are presented from calibration tests and simulations carried out to evaluate the failure behaviour of Huck Bolted connections. This paper presents an overview of the current state of the art in the rail industry and describes, through various case studies, the approach that Bombardier Transportation uses for validation of new vehicles. These case studies also show novel aspects of new vehicle design, which increase safety and highlight the commitment of Bombardier Transportation to a ‘design for crashworthiness’ approach to new passenger vehicles.