Field Test on Composite Foundation Incorporating Flexible and Rigid Piles

This paper presents three static load tests of composite foundation incorporating flexible piles, rigid piles and different cushion materials to clarify the load-displacement behavior of composite foundation. The results of static load tests indicate that the cushion made of stone and sand is not suitable because of a large pile penetration. As far as the influence of cushion material is concerned, the cushion made of sand, gravel and rubble with the maximum particle size of less than 20 mm and grouted with cement slurry can be used to fully mobilize the bearing capacity of each part of composite foundation, and modify the load transfer mechanism of the piles. Moreover, this type of cushion can reduce the overall settlement and ensure the uniform settlement of building.