Abstract
It is necessary to consider the wave propagating effect in the seismic design of long underground structures. In most cases, this effect is modeled as the phase delay of input ground motions. In this study, the input ground motions at many points were generated directly from the fault model, and the mechanism of phase difference occurrence was investigated. Furthermore, response soil strains of the irregular soil layer models subjected to different types of waves were calculated by use of FEM. These were (1) waves without phase difference, (2) waves considering phase difference and (3) waves generated from fault model. It was found that the results obtained from waves with phase difference have a problem in accuracy of the maximum strain compared to the waves directly generated from fault model.
