COMPUTATIONAL MODEL TO EVALUATE ACTIONS IN WHEELRAIL CONTACT INTERACTION

Resumo

Railway traffic is a big source of vibrations. Over the years, with higher freight capacity and speeds getting higher, excessive stresses are experienced by the subgrade. Then, stress waves propagate through the ground until buildings on the surroundings. This leads to considerable negative impacts on the neighborhood. On this context, this work is immersed in a broader scope of proposing an approach to create a model to simulate railway systems, with the main objective of predicting the vibration and stresses at the subgrade, in different situations, such as to predict the contact forces between the wheels and the rails. In this model, the dynamic characteristics of the vehicles and the contact between their wheels and the track are considered. The numerical model was solved using the software Giraffe. To simulate the traffic of a vehicle, a two-car train composition was modeled. One of the cars is loaded by an imposed torsion moment, applied on the axle of the wheels. A time-varying torsional moment was considered, so the simulation could reproduce an accelerating vehicle, the same vehicle in constant speed, as well as braking. The model, as it was proposed, represented the global mechanical behavior of the cars and it was possible to obtain the contact forces between wheels and a surface that represents the rails.