Up to now, the computer programs for studying dynamic behaviour of railway vehicles confine themselves to models with rigid wheelsets on a rigid, immovable track and to single-point-contact between wheel and rail. In this case tables for all interesting geometric functions can be used.

In the following paper the theory of a curving algorithm without these restrictions is introduced. The wheel-rail interactions are treated almost exactly. Within an iteration procedure linearized equilibrium equations and compatibility equations (or contact conditions) are solved simultaneously. The new method is therefore called simultaneous method. Finally some numerical results obtained by using the simultaneous method are presented. Especially the influence of 2-point-contact on the creepage forces and thereof on the wear process is pointed out.