(1. School of Civil Engineering，Lanzhou Jiaotong University，Lanzhou，Gansu 730070，China；2. State Key Laboratory of Frozen Soil Engineering，Cold and Arid Regions Environmental and Engineering Research Institute， Chinese Academy of Sciences，Lanzhou，Gansu 730000，China)
Abstract：In order to investigate the influence of pile bottom water on the stability of pile foundation in frozen soil，the concrete model piles and pile bottom water thermal device were made. The contrast experiment method was adopted by loading step by step to study the effect of pile bottom water heat on the rheological properties of frozen soil pile-soil，in which transfer curves of tangential freezing stress on pile body and pile tip resistance were obtained. Under the different load level，the influences of pile bottom water on the relative displacement between pile and soil，pile tip resistance，rheological characteristics of pile-soil，load transfer characteristics，and bearing characteristics of pile foundation were analyzed. The results show that the pile bottom water weaken the freezing strength of frozen soil in pile side and soil resistance at pile bottom，which increase relative displacement between pile and soil and pile-soil rheological effect. The pile bottom water can impact the load proportion of the freezing force and end resistance of a pile foundation，in which the pile foundation is excessively dependent on the tangential freezing stress on pile body to bear the load. Above effects increased with the load level result in a serious decline of bearing capacity of pile foundation.
吴亚平1，刘 振1，王 宁1，刘亚尊1，卢小强1，牛富俊2. 桩底水热效应对模型桩–冻土流变特性影响的试验研究[J]. 岩石力学与工程学报, 2016, 35(S1): 3424-3431.
WU Yaping1，LIU Zhen1，WANG Ning1，LIU Yazun1，LU Xiaoqiang1，NIU Fujun2. Experimental study of the thermal effect of pile bottom water on the rheological property of model pile-frozen soil. , 2016, 35(S1): 3424-3431.
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2016, Vol. 35 
