ABSTRACT
With the purpose of elucidating the horizontal subgrade reaction of piles in liquefied ground, this study conducted centrifuge model tests, which were a combination of shaking tests of a model ground and alternating load tests of a foundation constructed with four combined piles. In these tests, several types of seismic waves were applied to a model ground to examine the influence of preliminary shaking, depth, input waves, excess pore water pressure ratio, horizontal displacement, and ground water level on the horizontal subgrade reaction of piles. All test results were then collected to construct an estimating equation of the coefficient of the subgrade reaction continuing on to the non-linear area of the ground, and a relational equation of the subgrade reaction and displacement by using a hyperbolic function.
