Studies on the fluctuation characteristics of non-linear pile group coefficient

This paper presents the fluctuation characteristics of non-linear pile group coefficient. In this study, by evaluating the nonlinear influence coefficients between two piles, we have set up a non-linear pile group coefficient evaluation method which can evaluate non-linearity of soil between and around piles. This method is based on the pile group coefficient expressions which we proposed for the elastic soil in the past. The fluctuation characteristics of non-linear pile group coefficient obtained with this method was confirmed that it corresponds well to that of the analysis results of the three-dimensional finite element method. Based on this knowledge, we elucidated the phenomenon that with pile head displacement increases, the value of the pile group coefficient increases at first, but this value starts to decrease in the later.