Evaluation of Vehicle Running Safety on Railway Structures During Earthquake

The vehicle running safety on structures during an earthquake is drawing great attention due to the increased frequency of large-scale earthquakes in recent years in Japan. In order to enhance the vehicle running safety on structures during an earthquake, it is important to reinforce existing structures in an effective and efficient way. On this point, it is needed to identify potential weak structures for the running safety in continuous railway structures, understand the dominant factor that contributes to causing derailment, and provide an appropriate reinforcement to the existing structures. In this study, we investigated the influence of various parameters related to the vehicle running safety on structures during an earthquake with simple dynamic structural models using the analysis program DIASTARS III that can consider the dynamic interaction between railway vehicles and railway structures. We also conducted seismic vehicle running analysis on a model line with 4.8 km in length and identified the weak structures for the running safety. Additionally, we proposed an index that is calculated only from structural responses with an earthquake and evaluates the ease of derailment. It was observed that the index could identify the critical structures on the running safety and evaluate the dominant factor.