Structural Optimization Based on Numerical Analyses in the Development of New Highspeed Bi-Level Trains

In the development of the new bi-level train KISS nonlinear finite element analyses have been intensively applied to optimize the structure with respect to stiffness and strength as well as to crashworthiness. Models up to 3 million shell elements have been used to prove the strength of the load carrying structure with respect to the standard EN12663-1. By the use ofnumerical optimization codes the structure has been optimized with respect to lightweight engineering and with respect to a reduction of manufacturing time. Additionally, the fatigue strength of the structure, especially of the welds, has been evaluated with FEMFAT, a post-processor code from Magna Powertrain. The fatigue strength has been proven for typical load collectives representing the operational life for 40 years of operation. In simultaneous analyses the crash energy management structures have been optimized. All requirements of EN15227, the European crashworthiness standard, were successfully fulfilled. Comparisons with dynamic test results have shown that the numerical results are very close to the test data.