Deformation characteristics of energy piles subjected to horizontal load under heating–cooling cycles in sand

This paper examines the deformation characteristics of energy piles subjected to horizontal loads in sandy soil. A model energy pile was subjected to ten heating and cooling cycles. The temperature of the pile and soil around the pile, pile top horizontal displacement, pile strain, and horizontal soil pressure in front of the pile were measured. Furthermore, the bending moment and displacement of the pile body were calculated and analyzed. The results show that the horizontal displacement of the pile top consistently increased. The temperature variation caused significant changes in the pile body displacement, which increased in the heating process and decreased in the cooling process, showing an overall increasing trend. However, the increment of pile body displacement gradually reduced. The temperature variation considerably changed the pile's bending moment; the pile body's maximum bending moment appeared at a depth of 3.5 D (D is the pile diameter). The pile bending moment increased during heating but decreased during cooling. The pile bending moment increased with the number of heating–cooling cycles.