Abstract：The experimental study on the bearing capacity of heat-exchange piles in saturated clay in Ningbo was carried out under the conditions of 28 ℃，28 ℃→55 ℃，28 ℃→55 ℃→28 ℃. Heating (cooling) was carried out on the pile and soil firstly，and the static load test was then carried out to measure the temperature and pore water pressure，surface subsidence and displacement at pile top，axial force of pile and load-settlement data. The process of thermal consolidation and the mechanism of negative friction are investigated. Secondly，based on the model test，the finite element model for pile-soil considering the thermo-hydrodynamic coupling effect is established using software Abaqus. The calculated results are compared with the experimental results. The influence of temperature on the axial force and pile side friction of pile is discussed. The results show that the expansive deformation occurs in the pile and soil after heating，and the excess pore water pressure appears in the soil. With the dissipation of the pore pressure，the phenomenon of consolidation upon heating occurs in the soil，the settlement of soil is larger than that of the pile，the soil settlement takes place，and the negative skin friction resistance occurs because of the dragging load at the side of pile. With the increase of temperature，the strength of the pile is weakened along the depth direction，the strength of the soil after the heating consolidation is increased，the friction resistance of the pile is increased and the ultimate bearing capacity of the single pile increases with the temperature.
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2017, Vol. 36 
