Abstract: To deeply study the bearing capacity, settlement and failure mode mechanism of composite foundation with sand piles, single and group sand piles composite foundations with as well as contrast tests on the composite foundation with steel pipe piles are performed. designed and carried out in the laboratory model tests. The data about the load-settlement, pile-soil stress ratio, settlement-time and pile-soil stress ratio-time are obtained. The results show that the bearing capacity of the composite foundation with single steel pipe pile is lower, and the stress concentration on the pile top is more obvious, compared with that of the composite foundation with single sand pile. The composite foundation with group sand piles is of low settlement, high bearing capacity, significant time effect of settlement and pile-soil stress ratio, obvious pile replacement and full improvement of the bearing capacity of the soils between piles.