Abstract: Since 1982, the author has innovated the use of quicklime piles to stabilize soft clay foundations of three housing projects in HangzhouIt has been proved that the quicklime pile is really an effective means for stabilizing soft foundation by eleven 2m×2m field plate bearing tests with collaborated vane tests and laboratory tests. The water content and void ratio of soft mucky clay could be considerably reduced and the vane shear strength was increased 1.13-4.50 times after treatment. The plate bearing tests demonstrated that the allowable bearing capacities of miscellaneous fills were increased 1.58-4.14 times after treatment.The quicklime pile has been used for the first time in three six-storey housing projects in Hangzhou. According to the weasuring results of pore-water pressures, contact pressures under the foundations and settlements of buildings it was proved that the buildings settled uniformly and performed well.The technical and economical results of the stabilization methods of house foundations commonly used in Hangzhou are also presented in this paper. The economical analysis indicated that the cost cost could be reduced by an amount of 40%-60% if quicklime piles were used instead of precast concrete piles or cast-inplace concrete piles under the same geological conditions.