An evaluation method for train-speed dependency of Shinkansen-induced vibration

Speedups of Shinkansen-trains are in progress on several Shinkansen lines. To preserve the environmental conditions along the Shinkansen track, it is necessary to assess the effect of increased speeds on ground vibration. An average increment of Shinkansen- induced ground vibration has already been estimated for each Shinkansen line with the previous measurement results; however, train-speed dependency varies much within one line. Therefore, a method for the train-speed dependency at each point along the line is required to estimate the cost and the length of needed countermeasures. In this paper, the characteristics of Shinkansen-induced ground vibration are discussed first. Then, an evaluation method for the train-speed dependency of train-induced vibration is proposed with simple models of dynamic characteristics of the ground, excitation force, and the periodic effect of axel loads.