Behaviour of thermal piles in loose/very loose granular materials

Evidence from grain silos and integral bridges shows that relatively rigid structures in contact with loosely packed soils subjected to thermal cycles, can fail due to the increased packing density caused by temperature induced movements within the soil.

This phenomenon has not been investigated in the context of geothermal piles. RWTH Aachen Chair of Geotechnical Engineering has a large cylindrical pit of 6m depth and 3m diameter where bearing capacity tests will be carried at almost real scale.

The project will investigate the hypothesis that thermal cycling can lead to failure of piles from increased soil density. It will consist of numerical modelling anchored on the University of Melbourne’s previous developments,  and of experiments primary arising from the near real scale testing at RWTH complemented with (thermal only) testing of pile at Melbourne University’s new Fisherman’s Bend campus, dominated by (saturated) high void ratio normally consolidated clays. The project aims at evaluating the impact of the presence of loosely packed soils in the bearing capacity of geo-thermal piles and temporal changes in thermal performance.

Principal Investigators:

The University of Melbourne: Associate Professor Guillermo Narsilio

RWTH Aachen: Prof. Dr. Raul Fuentes