An efficient numerical method for the vehicle-bridge nonlinear dynamic interaction

This study aims at providing an efficient and accurate method for the time history simulation of the vehicle-bridge dynamic interaction. With the geometric nonlinearity in wheel-rail contact fully considered, a simplified assumption was adopted that vertical wheel-load fluctuation has no influence on the lateral wheel-rail interaction. The wheel-rail creep forces are computed using Kalker's theory, and the normal forces are solved from wheel-set vertical and torsional equilibrium equations. The method limited the number of nonlinear parameters for each wheel-set to five. In addition, mode superposition method is adopted for bridge responses to minimize the overall system DOFs. The virtual work principle method is used to derive the system matrix. Numerical examples show that the present method gives results comparable in terms of accuracy to that using a more complex model. But it is at least 50 times faster than the detailed model. The efficiency and accuracy of the proposed method will make it suitable in the reliability-based vehicle-bridge interaction analyses.