地盤一杭基礎系の動的相互作用効果を考慮したハイブリッド実験と地震観測事例の比較

Abstract

We developed an algorithm to study non-linear seismic soil-structure interaction through a hybrid procedure using pseudo-dynamic testing method which is modified to take into account frequency dependence and developed for foundation-soil systems.Four large scale pile foundations, 1 -pile, 2 -pile, 3-pile and 2 -pile models, were used.For piles and pile group design purposes, the system's responses in translation and rotation are considered to be independent of the axial deformations.In order to investigate and estimate this coupling and to study on the effect of increasing dead loading on the swaying-rocking response of piled foundations, the 3-pile group model was used.Four dead loadings of 10, 20, 30 and 40 ton were applied to increase the axial loads in the piles.Some opportunities to observe seismic data for pile foundations were provided when earthquakes occurred at the site of expriments.The comparison between the computed and measured motions provided confidence in understanding the foundation mechanism and on the usefulness of the simplified modeling used.