Abstract
This paper deals with the critical speed optimization of a rail vehicle system moving in curved track with relatively high speed. Indeed the roll motion of the car body will be included in the dynamic model in order to study its effects. Based on the structural characteristics of the rail vehicle and its curved motion, a critical speed optimization as a function of the radius of curvature and the rail vehicle design parameters is performed using the genetic algorithms. The safety criterion is evaluated using the derailment angle. The outcomes of this work could help the designer in his choice of the adequate design parameters yielding the best compromise between critical speed and radius of curvature.