The thermo-mechanical behavior of a floating energy pile installed in sand is investigated by the coupled multi-physical finite element method. The results show that the heating load induces the additional axial compressive stress in the pile

the negative side frictional resistance near the pile head and the uplift of the pile head. On the contrary

the cooling load induces the additional axial tensile stress in the pile

the positive side frictional resistance near the pile toe and the settlement of the pile head. For the given thermal load

the mechanical response of energy pile mainly depends on the magnitude of mechanical load on pile head. Thermally induced additional axial stress in energy pile increases firstly with increasing the mechancal load

and then keeps constant when the mechancal load is greater than a certain critical value. The temperature change in the subsoil decreases rapidly in radial direction

and the influence distance of the thermal load in the subsoil is about 20 times pile diameter from the side of the pile. Furthermore

the restraint condition on the pile head has significant effect on the thermo-mechanical response of energy pile. The larger the stiffness of the pile head

the greater the value of the thermally induced axial stress.