Abstract: As composite foundation with multi-element pile,the under-rammed bored pile,which composites the cast-in-place pile in upper part and the rammed bulb pile in under part,is used in an engineering by combining with the rammed and compacted lime-waste-soil pile.The function of this composite foundation lies in,improving the bearing capacity of ground soil and controlling the settlement of building by the under-rammed bored pile,and compacting the soil around pile and improving the compressibility of artificial soil by the rammed and compacted pile.The best plan of ground treatment from analysis and calculation can provide some valuable informations for the similar engineering.