Effect of vertical ground motion on earthquake-induced derailment of railway vehicles over simply-supported bridges

• Published in: Journal of sound and vibration 2016-11, Vol.383, p.277-294
• Main Authors: Jin, Zhibin, Pei, Shiling, Li, Xiaozhen, Liu, Hongyan, Qiang, Shizhong
• Format: Article
• Language: English
• Subjects: Bridge–train coupled vibration; Derailment; Railway vehicle; Vertical ground motion
• ISSN: 0022-460X; 1095-8568
• DOI: 10.1016/j.jsv.2016.06.048

The running safety of railway vehicles on bridges can be negatively affected by earthquake events. This phenomenon has traditionally been investigated with only the lateral ground excitation component considered. This paper presented results from a numerical investigation on the contribution of vertical ground motion component to the derailment of vehicles on simply-supported bridges. A full nonlinear wheel–rail contact model was used in the investigation together with the Hertzian contact theory and nonlinear creepage theory, which allows the wheel to jump vertically and separate from the rail. The wheel–rail relative displacement was used as the criterion for derailment events. A total of 18 ground motion records were used in the analysis to account for the uncertainty of ground motions. The results showed that inclusion of vertical ground motion will likely increase the chance of derailment. It is recommended to include vertical ground motion component in earthquake induced derailment analysis to ensure conservative estimations. The derailment event on bridges was found to be more closely related to the deck acceleration rather than the ground acceleration. •The derailment of vehicles on bridges during earthquake was evaluated based on wheel–rail displacement instead of the traditional wheel–rail forces.•A suit of 18 ground records included in the simulation makes it possible to evaluate the derailment event from a statistical point of view.•The vertical ground motion was included, and found to have notable effects on the derailment events.•The deck acceleration was found to be a good intensity indicator for evaluating vehicle derailments on bridges.