Abstract: The bearing capacity mechanism of pile foundation under combined horizontal loading and vertical loading is researched through several centrifugal model tests. The results indicate that under the same displacement,the horizontal bearing capacity of pile foundation decreases with the increase of vertical load. Under the same horizontal load,the horizontal displacement of pile head increases with the increase of vertical load. The larger the vertical load is,the bigger the inclination of pile is. When the pile foundation is under the action of combined vertical load and horizontal load,the two loads are affected by each other. The interaction of horizontal load H and vertical load V must be considered in the design of pile foundation.

Key words: centrifugal model test, combined load, bearing capacity mechanism, pile foundation