Energy absorption design study of subway vehicles based on a scaled equivalent model test

Abstract

To obtain the characteristics of collision energy absorption and improve the passive safety of subway vehicles, the energy absorption design of subway vehicles was studied based on a one-seventh-scale model crash test. A full-size three-dimensional model of a subway vehicle was established using the multibody dynamics software MADYMO. The simulation results of the dynamics model were scaled down according to the similarity coefficients. By comparing the simulation results with the scaled model test results, the maximum error of deformation was 2.10 and 4.35% for the head car and the maximum deforming middle car, respectively, and the energy absorption error was found to be 8.75 and 5.70% for the head car and the maximum deforming middle car, respectively. The results indicate that the collision dynamics model of subway vehicles is relatively accurate. Next, based on this dynamics model, a full factorial experiment was designed to study the effects of the marshalling, mass and crushing tube’s plastic deformation platform force on the energy absorption of subway vehicles. The calculation results were fitted by multiple linear regression functions. Finally, the authors obtained the crash energy absorption formulas for the subway head car with an accuracy of 98.42% and for the maximum deforming middle car with an accuracy of 95.31%. These formulas can be applied to the preliminary design of subway vehicles and offer guiding significance for the parameter design of subway vehicles’ energy-absorbing devices.