• Whell\Rail Contact
• NASTRAN
• FEMBS
• SIMPACK
• Flexible Bodies
• Track fatigue
• Bogie
• Comfort
• Guyan reduction
• Craigh-Bampton reduction

The aim of the thesis is to highlight the effects of bodies flexibility concerning the Running Dynamics requirements and the Structural requirements and how such aspects could be taken into account in an integrated design process focused on the optimization of the vehicle design in terms of Comfort, Safety, Track fatigue and Bogie frame design.
A simplified multi-body system of the vehicle has been developed utilizing the software SIMPACK and thanks to the interaction between SIMPACK module, FEMBS, and the commercial finite element softwares (e.g. I-DEAS as pre and post-processor and MSC NASTRAN as solver), the flexible bodies, as carbody, wheelset, bolster-beam and bogie-frame, have been implemented.
In the integration process of the flexible body into a multi-body system, a critical step is the reduction of the finite element model of the body to decrease the computational burden. For such reason an analytical verification, in order to validate the reduced FE-model with respect to the full FE-model, has been planned and implemented to provide the company with a powerful and useful design tool.