Experimental and numerical investigations of the behaviour of a heat exchanger pile

TLDR

Geothermal concrete geostructures transfer ground energy to building environments via fluid‑filled pipes, offering an environmentally friendly heating and cooling solution. The study investigates how thermal effects increase loads on a geothermal concrete pile under thermo‑mechanical conditions. Coupled multi‑physical finite element modelling simulates the pile’s thermo‑mechanical response to experimental loading. Experiments reached a 21 °C temperature rise and 1300 kN load, and the model accurately reproduces these thermo‑mechanical effects. © 2006 John Wiley & Sons, Ltd.

Abstract

The geothermal use of concrete geostructures (piles, walls and slabs) is an environmentally friendly way of cooling and heating buildings. With such geothermal structures, it is possible to transfer energy from the ground to fluid-filled pipes cast in concrete and then to building environments. To improve the knowledge in the field of geothermal structures, the behaviour of a pile subjected to thermo-mechanical loads is studied in situ. The aim is to study the increased loads on pile due to thermal effects. The maximum thermal increment applied to the pile is on the order of 21°C and the mechanical load reached 1300 kN. Coupled multi-physical finite element modelling is carried out to simulate the observed experimental results. It is shown that the numerical model is able to reproduce the most significant thermo-mechanical effects. Copyright © 2006 John Wiley & Sons, Ltd.