Abstract：The special engineering feature of loess leads to the collapsible deformation of the pile foundation when the soil around piles is saturated. The deformation usually leads to negative friction and reduces bearing capacity of piles. Based on the loading test before and after saturation of pile foundation of Shaanxi Zhichuanhe Bridge，the bearing capacities before and after saturation are analyzed. It is found out that effect of surface water on the property of bearing capacity of pile foundation in loess area is significant. The regularity of settlement of pile foundation and soil around is summarized. The results can provide references to the design and construction of pile foundation in loess area.
