Abstract: Based on the self-developed single pile-freezing soil model test device, the simulation experiment about the interaction between unidirectional freezing soil and pile was conducted. With the same water content, the variation trend of the temperature field of the soil around the pile, the uplift displacement at the pile top and the lateral friction at the pile base in the freezing soil were studied when the freezing temperature was -5℃, -10℃, and -15℃ respectively. The experiment results show that during the unidirectional freezing process, the temperature of the soil around the pile is changed gradually and is related to the freezing temperature; the uplift displacement at the pile top undergoes three stages, i.e., early freezing stage without obvious displacement, rapid growth stage and gradually steady stage; and the lower the freezing temperature, the larger the uplift displacement at the pile top; the distributions of the pile side friction with different freezing temperatures exhibit the similar law that the positive and negative frictions occur alternatively.

Key words: geotechnical engineering, freezing soil, unidirectional freezing, pile, side friction, uplift displacement

摘要： 采用自行设计的 单桩-正冻土模型试验装置，对单向正冻土和桩的相互作用进行了模拟试验。试验研究了相同含水率下，冻结温度分别为-5、-10、-15 ℃时，正冻土中的 桩周土体温度场，桩顶上拔位移和桩基侧摩阻力的变化趋势。试验结果表明：在单向冻结过程中，桩周土体温度呈渐变趋势，且与冻结温度相关；桩顶位 移经历3个阶段，即冻结初期无明显位移阶段、迅速增长阶段及逐渐平稳阶段，且冻结温度越低，桩顶上拔位移越大；不同冻结温度的桩周摩阻力沿桩身 变化趋势类似，即摩阻力呈现正、负交替分布的状态。

关键词: 岩土工程, 正冻土, 单向冻结, 桩, 侧摩阻力, 上拔位移