The thickness of the sluice foundation of Xinglong Hydrojunction Project on Hanjiang River, a deep fine sand layer, is 25 m. To solve the liquefaction problem of saturated sand and large settlement of the foundation, the foundation was treated by using cement-soil mixing pile rather than the dynamic consolidation or vibroflotation method through comparison. In the current cases of mixing pile, the viscous soft soil with small frictional resistance are treated; however, the treatment of fine sand layer with large frictional resistance and running groundwater are rare. Therefore, the laboratory experiment and in-situ test of cement-soil mixing pile was conducted, which proved that this mixing pile is suitable for the treatment of the sluice foundation of Xin-glong Hydrojunction Project. The piles are arranged in grid with the replacement rate of 20%. The quality of the mixing pile meets the requirement and the deformation monitoring shows that the settlement control meets the design requirement.%汉江兴隆水利枢纽泄水闸深厚粉细砂土层地基厚约25 m。为解决地基沉降量大与饱和砂土震动液化问题，经对强夯法、振冲法和水泥土搅拌桩法等处理方案比选后，决定采用水泥土搅拌桩对地基进行处理。现有搅拌桩工程实例大多是处理摩阻力较小的黏性软土，对于处理摩阻力大和存在流动地下水的粉细砂层尚属少见。为此，对水泥土搅拌桩进行了室内和现场试验研究，证实了搅拌桩适宜于处理兴隆泄水闸粉细砂地基。搅拌桩采取格栅式布置，置换率约20%。施工完成后的搅拌桩质量检测全部合格，变形监测结果表明，沉降量控制满足设计要求。
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