Study on the influence of trains on the seismic response of high-speed railway structure under lateral uncertain earthquakes

At present, specific earthquake motion is often used for analyzing the influence of trains on high-speed railway structure; however, the uncertainty of earthquake motion is rarely taken into consideration. In this study, on the basis of considering the uncertainty of earthquake motion, and taking a simply-supported beam with CRTS II track system and CRH2 high-speed train in China as the research objects, a finite element analysis model of vehicle-bridge coupled model was established and verified by tests. The influencing mechanism of the trains on structural response under the action of uncertain earthquake was analyzed, and the range of the influence levels of trains on seismic response of structure was calculated. The research findings show that under the effect of earthquake, the presence of trains decreases the responses of piers and bearings, while increases the response of track structure. With increasing peak ground acceleration, the effect of trains on the track structure deformation increases, while that on the bending moment of piers, shearing force, and bearing deformation all decrease. The increase in train speed will not significantly affect the seismic response of structures. The ratio of seismic response between the operating conditions with and without vehicles was kept within a certain range, so that the demand range for seismic response under the operating condition with vehicles can be approximately simplified.

Automated summary

The study analyzed the influence of trains on high-speed railway structures under seismic action by considering the uncertainty of earthquake motion. It found that the presence of trains can decrease the responses of piers and bearings, while increasing the response of track structures. The study also showed that the increase in train speed has no significant effect on the seismic response of structures, and the demand range for seismic response under operating conditions with vehicles can be approximately simplified.