Research on the evaluation criteria for safety state of train operation based on the scaled model

Abstract To accurately predict the train operation state through the test results of the scaled vehicle-track test platform, based on the similarity theory and vehicle-track coupling dynamics theory, the similarity criterion of vehicle-track coupling dynamics system was proposed, and the dynamics models of vehicle-track system in scaled and full scale were established. The running characteristics of wheels under the critical state of derailment were analyzed, and a dynamic evaluation criterion of relative wheel-rail displacement (DEC-RWRD) was proposed. The results show that based on the proposed similarity criterion, the predicted displacement responses of the scaled vehicle-track model is consistent with that of the full scale vehicle. The differences in the accuracy of different train safety evaluation criteria by the scaled vehicle-track model are investigated, and the accuracy of the evaluation can be improved by DEC-RWRD. The combination of DEC-RWRD and the existing train dynamic monitoring methods can realize the prediction and the evaluation of trains’ operation safety by the scaled vehicle-track test platform. The results can provide theoretical support for the dynamic evaluation of the safety status of high-speed train operation under severe line conditions and the experimental study of the whole process of derailment.