Extended Abstract e 5 th Joint International Conference on Multibody System Dynamics June 24 – 28, 2018, Lisbon, Portugal Wear and Rolling Contact Fatigue: development of an innovative tool for simultaneous wheel and rail damage evaluation Elisa Butini 1 , Lorenzo Marini 1 , Martina Meacci 1 , Enrico Meli 1 , Andrea Rindi 1 1 Department of Industrial Engineering, School of Engineering, University of Florence, {elisa.butini,martina.meacci,lorenzo.marini,enrico.meli,andrea.rindi}@unifi.it Wear and the rolling contact fatigue are the main responsible for a decrease in wheels and rails life. A change in wheel and rail profile directly influences the vehicle dynamic behavior, comfort and stability. It impacts also on the economical aspect, increasing the costs related to maintenance operations necessary to re- establish wheel and rail profiles and to ensure a running in safety condition. Hence, a suitable madel able to predict rail and wheel profile evolution and fatigue damage can be a powerful tool in maintenance planning optimization and a useful aid in a better managing of wheel and rail damage. To this purpose, the Authors present an efficient and innovative modelling approach suitable for different railway scenarios, that combines togheter a wear model to evaluate the wheel and rail profile evolution and a RCF crack prediction model. e proposed model is capable to predict simultaneosly the profiles shape evolution due to wear and the total RCF damage both for the wheel and for the rail. anks to the numerical efficiency and accuracy of wear and RCF model, an online implementation within vehicle multibody models it is possible. Fig. 1 Model general layout More specifically, the general layout of the whole model (see Fig. 1) is made up of three main parts: the dynamic block, the wear model and the RCF crack depth prediction model. e first block consists of the 3D multibody model of the benchmark vehicle (modelled in Simpack Rail environment and used to accurately reproduce the dynamics of the vehicle) and of the global contact model, developed by the Authors in previous works [1] and implemented in C/C++, creating a loop. e global contact model exploits, for the contact point detection, a very efficient algorithm, while the contact forces (normal and tangential) and the global creepages on the contact patch are calculated through Hertz’s and Kalker’s global theories. Starting from the outputs of the dynamic simulations (position and shape of the contact patches, contact pressures, etc.), the wear model, based