Abstract
Response displacement method have been used for evaluating seismic response values of bridge, viaducts and underground structures. At this time, it is necessary to evaluate ground displacement as seismic action and it is evaluated from the natural period of surface ground which is calculated from the initial stiffness of each soil layer. However, in case of inputting the strong ground motion, the nonlinearity of surface ground has a large effect on ground displacement.
Therefore, in this study, we propose an evaluation method of ground displacement considering the shear strength of surface ground, which is called ground strength ratio Kf, for the improvement of the conventional method. Kf can be easily estimated from the information of general soil surveys. So, this method is considered to be effective method as an evaluation method of ground displacement for applying response displacement method.
