Pile foundation engineering energy storage

What is an energy pile?

Energy pile is a deep foundation that combines two functions, transferring structural loads to the soil and serving buildings thermal needs. It is an innovative technology that also provides cost savings and environmental protection by reducing fossil energy utilization.

Are piles energy sourcing structures cyclic?

As shown in this study, the use of piles as energy sourcing structures result in cyclic changes in stresses and strains in and around the pile which are governed by the magnitude and combination of the superimposed coupled loads and the type of restraint on the pile.

How is heat extracted from a pile foundation?

The heat is extracted from or injected into the ground through the circulation of heat carrier fluid that flows in energy loops attached to the reinforcement cage of the pile foundation elements.

Why should CFG energy piles be designed for cooling?

Cooling cycle induces pronounced pile settlement and a decrease in its bearing capacity. Thus, CFG energy piles should be carefully designed for cooling purposes. Increase in soil temperature results in an increase in pile creep rate.

What is the displacement of an energy pile?

The displacement of an energy pile is 2.35 times that of a non-energy pile after 50 years of continuous heat injection operation. Long-term energy pile displacement can be minimised by limiting the initial settlement. During heating and cooling operations, the thermal axial strains observed were within acceptable limits.

How does heating and cooling affect pile load distribution?

It is an innovative technology that also provides cost savings and environmental protection by reducing fossil energy utilization. In this review study, thermal changes due to heating and cooling cycles that significantly affect the load magnitude and distribution throughout the pile, especially the shear stress and axial load, are discussed.