Design of thermo-active geo-structures as a renewable energy solution

Andrew Minto is carrying out research towards a PhD at the University of Dundee. Andrew’s research focuses on the behaviour of thermo-active diaphragm walls in clay soils, looking at the energy efficiency of such structures and how the cyclic thermal loads affect the soil behaviour surrounding the wall by using highly-instrumented centrifuge models.

Thermo-active geo-structures are becoming more common as a renewable energy solution which utilises shallow geothermal energy to provide heating and cooling to buildings. These geo-structures produce a significant reduction in carbon omissions and whole-life costs, while the additional cost to install is insignificant given these structures are already required to support the structure.

Underground construction in urban cities where space is at a premium can produce significant challenges, which can be exacerbated by the addition of cyclic thermal loads introduced by energy geo-structures, particularly in clay soils which are particularly sensitive to temperature changes and where the volumetric expansion/contraction of the soil is dependent on stress history. The complex soil-structure interaction is further complicated by the tendency of the geo-structure to expand and contract as it is heated and cooled, to provide heating and cooling to the building it supports.

This presentation will discuss the research which has been carried out to date on thermo-active piles and diaphragm walls, and will present some centrifuge test data from tests carried out as part of Andrew’s PhD project.