Mechanical behaviour of energy piles in dry sand

In this study, for investigating the mechanical behaviour of energy pile, the behaviour of an axially loaded pile under thermal cycles was investigated using a physical model. After applying the axial load by dead weights on the pile's head, the pile was heated from 25°C to 50°C and subsequently cooled to 25°C. Four tests (corresponding to four values of axial load) were performed and two temperature cycles were undertaken in each test. When low axial loads were applied, the heating induced heave and cooling induced settlement of the pile's head. In the case of higher axial loads, the heave of the pile's head, obtained during heating, was lower than the thermal expansion of the pile demonstrating the settlement of the pile's toe.