COMPARATIVE ANALYSIS OF TWO ALGORITHMS FOR WHEEL-RAIL CONTACT STRESS

The comparative analysis of Kalker’s theory of three-dimensional elastic bodies in the rolling contact with non-Hertzian (CONTACT) and the finite element method is conducted. These two algorithms were used to calculate the contact area, the contact pressure and contact stress of wheel and rail. In the investigation, the wheel profile LMa used in the high speed train of China (CRH2) and its worn profile measured after a running of 100000 kilometers are chosen to match with 60kg/m rail of China. The results show that the wheel-rail contact area calculated by CONTACT is less than that calculated by the finite element method (FEM), but the maximal contact pressure and maximal equivalent stress calculated by CONTACT are larger than those calculated by FEM, especially when the wheel flange contacts with a rail gauge corner. The difference between the results of CONTACT and FEM is very small when the significant dimensions of the contact area are small, compared with the relative radii of curvature of wheel and rail at the contact point. Multi-contact is easy to occur when worn wheel profile contacts with a rail profile. The difference between the results of CONTACT and FEM is significant when multi-point contact occur. Therefore, CONTACT is not suit for the case of the multi-point contact of wheel and rail.