The influence of cushion on loading behavior of the composite foundation with compacted soil-cement pile was studied by static loading in-situ. The result of test shows that the thickness and character of the cushion have an important impact on the loading and deformation characteristics of composite foundation. With increasing of the cushion thickness
the loading ratio of the pile is decreasing
but the ratio of the soil is increasing. The pile-soil stress ratio reduces with the increasing of the cushion thickness. On the other hand
the more the character of the cushion is strong
the greater the ability of adjusting deformation
the thinner the cushion thickness. The test result of different thicknesses and two types of cushion shows that the best thickness is of 0.2-0.3 m.