INFLUENCE OF THE NUMBER OF TRAIN CARRIAGES ON TRAIN-INDUCED GROUND VIBRATIONS

Abstract

Trainload is characterized by a number of factors such as axle load magnitude, number of carriages, train speed, etc. These factors likely contribute to the ground vibration induced by a high-speed train. While vibration effects associated with train speed have received much research attention in the literature, limited attention has been paid to the effects associated with the number of train carriages. In this study, we investigate how the number of train carriages affects ground vibrations caused by a high-speed train. A finite element model is used to simulate the vibration of a layered ground caused by a Shinkansen train moving at a speed of 70 m/s (252 km/h). There are 8 cases of trainload considered, and each case corresponds to a number of train carriages. The simulation result shows that the number of train carriages has a significant influence on the amplitude of ground vibration. The influence is more pronounced for locations near the excitation source. When the train has 4 or fewer carriages, the vibration amplitude increases with increasing the number of train carriages. However, when the train has 4 or more carriages, the vibration amplitude remains unchanged. It is therefore recommended that in a simulation of train-induced ground vibration, we should only use a sufficient number of train carriages (about 4 to 5 carriages). If more train carriages are used, we still get the same result, but the computational cost increases significantly.