Abstract
Large scale shaking table experiments of pile foundation have been carried out to investigate dynamic interactions between pile and soil. The deposit of K asumigaura sand, naturally dried, is prepared in a laminar box of 12m, 6m and 3.5m in length, height and width, in which 4 steel piles of 6m and 0.32m in length and diameter are installed. The force of interaction between soil and pile is calculated from the 2nd derivative of moment on the pile, the relative displacements between the deposit and piles are obtained from the accelerations measured. It has been found that the coefficients of dynamic interaction increase with depth proportionally, decrease with shaking level but vary slightly with the frequency. Most of damping is attributed to the nonlinearity of soil so that damping ratio increases with shaking level.
