Abstract
In seismic design of railway structures, a folding angle of railway track must be checked in order to secure the train running stability. On irregular grounds, the angle are strongly effected by surface waves which are generated around a dipping basement. Therefore, a method must be presented for calculating the folding angle taking into the ground irregularity account. In this paper, characteristics of out-of-plane vibrations on the irregular ground are clarified by using FEM analyses and the effects of ground irregularity on folding angles of raiway track are investigated by using the calculated earthquake ground motions.
