Simulation of train-turnout interaction and plastic deformation of rail profiles

Railway turnouts (switches and crossings) require more maintenance than other parts of the railway network. Multiple wheel-rail contacts are common, and impact loads with large magnitudes are generated when the conventional wheel-rail contact conditions are disturbed at various locations along the turnout. The dynamic interaction between train and turnout is simulated in order to predict the forces and creepages in the wheel-rail contacts, and the sizes and locations of the contact patches. Furthermore, the change in rail profile because of plastic deformation is calculated by finite element analysis at a selected position along the switch rail. Contact loads and contact locations, taken from the vehicle dynamics simulation, are then used as input data in the finite element analysis. The objective of the study is to gain knowledge about the influence of different damage mechanisms on the life of a turnout. This is useful in an optimization of turnout geometry with the purpose to improve vehicle ride dynamics and to decrease maintenance costs.