Centrifuge modeling of energy foundations – effect of seasonal temperature fluctuation and soil state

Energy foundations can reduce carbon footprint and lead to energy savings. Understanding the process of heat migration in soil is therefore of great interest in the field of geotechnical engineering. However, limited literature exists on the thermo-dynamic interaction and structural performance of an energy foundation and the surrounding soil. Lab testing of energy foundations remains inexpensive compared to field tests; however lab tests cannot easily simulate representative in-situ stress conditions. This can be resolved by using a geotechnical centrifuge to correctly mimic the stress gradient of the self-weight of the soil. A series of centrifuge models of energy foundations in different soil states (dense and loose) have been tested. Representative seasonal temperature fluctuations in the UK are used as the benchmark in this study. A total of three years of heating/cooling cycles are modelled and foundation response is captured by means of embedded temperature sensors at different distances away from the thermal foundation.