ABSTRACT
The formulation of the contact forces that describe the dynamic interaction between the wheel and the rail is one of the fundamental problems that must be addressed in developing a multibody system formulation for railroad vehicle systems. Various contact models are used in different computer formulations to describe the wheel/rail interaction. In this chapter, the rigid body contact is discussed, with particular emphasis on Hertz theory and the formulations of the wheel/rail creep forces. The definitions and concepts introduced in this chapter will be used in the formulation of the normal and tangential forces that describe the wheel/rail interaction.
