Model tests on thermal response of phase-change pile in saturated silt foundation

The phase-change concrete energy pile is prepared by using the composite phase-change materials, and the thermal response model tests on the phase-change pile is carried out in silt. On this basis, the finite element model for energy pile is established, and the thermal response characteristics of the phase-change pile and ordinary pile are compared and analyzed. the results show that during the thermal response process in summer (10 ℃→40 ℃→10 ℃, 10 ℃→25 ℃→10 ℃) and winter (16 ℃→5 ℃→16 ℃). The variation range of temperature of the phase-change pile is smaller than that of the ordinary pile, which is helpful to alleviate the thermal accumulation effects of the soil around the pile. The addition of phase-change ceramsite reduces the displacement of the energy pile caused by the pile-soil thermal expansion during the process of heat exchange.