On the Effect of Track Irregularities on the Dynamic Response of Railway Vehicles

Abstract

<p> The steady state response for models of an actual six-axle locomotive running on a sinusoidally irregular track is investigated. Three mathematical models are set up, a simplified model which assumed no springing or damping of trucks or motors, and no creep forces, a full model for the "stationary" vehicle in which creep forces are assumed negligible and a full model for the "moving" vehicle, which creep forces, gravity stiffness effects and wheel tread profiles are considered. </p> <p> The steady state response of the vehicle components to varying input frequencies is calculated and the response curves are computer plotted in each case. The natural frequencies for the simplified and the full model are also calculated. For the "moving" vehicle responses for the cases of new and worn wheels are obtained. Effect of creep and wheel tread profiles is studied. </p> The accuracy with which each of the devised models describe the performance of the real railway vehicle is compared. A discussion of the conclusions drawn from the analysis, including the applications to the design of high speed railway vehicles is given. Much attention was devoted to the development and testing of five computer programs for which simplified flow charts are given in Appendix V. </p>