Analysis of the Dynamic Forces in the Crossing of Railway Turnouts

摘要

The influence of wheel/rail geometry and track stiffness on dynamic forces in the turnout crossings are studied. The dynamic interaction between the railway vehicle and turnout is analysed in the time domain using the 2D finite element model (DARTSNL). A method to represent the vertical rail geometry of a turnout crossing based on visual images is suggested. It is shown that the vertical rail geometry obtained such a way is in agreement with measurement results.The results of the numerical simulations reveal that wheel and rail geometry significantly affect the dynamic forces in the crossing. It is also shown that by increasing track elasticity between rail and sleepers the dynamic forces (and therefore damage to crossing nose) can significantly be reduced. Increase of the track elasticity on the lower levels e.g. by introducing under sleeper pads, ballast mats etc. has very limited effect on the wheel-rail forces. Yet these elements can be used to reduce the dynamic forces on ballast and subgrade. The developed numerical model can be used for determination of optimal elastic properties of a turnout.