Abstract: Centrifuge model tests were carried out for a pier constructed on a deep soft ground with a combination of long pipe piles, dikes, soil foundation and other associated structures. This paper presents the test results of the deformation of the dike, the bending moment and soil resistance of the pile near the dike at different construction and operation periods. Since the 3-D effect of pile groups and the consolidation processes of the soft foundation can be simulated in the centrifuge modeling at the same time, the test results offer an economical and effective alternative to large scale field tests in verifying the numerical analysis and determining the behavior of pile groups.