Abstract
Energy piles are piles equipped with heat exchange pipes through which a heat-carrying fluid circulates and exchanges heat with the ground. This technology couples the structural role of classical pile foundations with the energy supply of heat exchangers. During heating and cooling processes, the temperature of the energy pile and the ground will change seasonally. Due to the thermal displacement incompatibility between the pile and the soil, the load transfer mechanism of energy piles is different to that of conventional piles which are only subjected to mechanical loadings. In order to improve the understanding of the long-term performance of energy piles in sands, a series of coupled thermal-stress finite element analyses were carried out. In the analyses, the bounding surface plasticity model was used to describe the nonlinear behavior of sands under monotonic and cyclic loadings. The thermally induced displacement and axial force in the pile, the thermally induced change in the soil stress, and the ultimate pile resistance after thermal cycles were discussed. The numerical results indicated that the soils around the energy pile were subjected to cyclic mechanical loadings caused by repeated temperature variations. The accumulation of plastic strains resulted in a significant increase in the pile head settlement for the free head pile and a significant decrease in the pile head reaction force for the restrained head pile. During the reloading stage, the thermally induced decrease in the shaft resistance was compensated by the soil dilatancy, the ultimate pile resistance after thermal cycles did not change remarkably.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Adam D., Markiewicz R.: Energy from earth-coupled structures, foundations, tunnels and sewers. Géotechnique 59(3), 229–236 (2009). https://doi.org/10.1680/geot.2009.59.3.229
Bardet, J.P.: Bounding surface plasticity model for sands. J. Eng. Mech. 112(11), 1198–1217 (1986). https://doi.org/10.1061/(ASCE)0733-9399(1986)112:11(1198)
Bourne-Webb, P.J., Amatya, B., Soga, K., Amis, T., Davidson, C., Payne, P.: Energy pile test at Lambeth College, London: geotechnical and thermodynamic aspects of pile response to heat cycles. Géotechnique 59(3), 237–248 (2009). https://doi.org/10.1680/geot.2009.59.3.237
Brandl, H.: Energy foundations and other thermo-active ground structures. Geotechnique 56(2), 81–122 (2006). https://doi.org/10.1680/geot.2006.56.2.81
Di Donna, A., Laloui, L.: Numerical analysis of the geotechnical behaviour of energy piles. Int. J. Numer. Anal. Meth. Geomech. 39(8), 861–888 (2015). https://doi.org/10.1002/nag.2341
Goode III J.C., Zhang M., McCartney J.S.: Centrifuge modelling of energy foundations in sand. In: ICPMG2014—Physical Modelling in Geotechnics: Proceedings of the 8th International Conference on Physical Modelling in Geotechnics 2014 (ICPMG2014), Perth, Australia, 14–17 January 2014, pp. 729–735 (2014). https://doi.org/10.1201/b16200-100
Kalantidou, A., Tang, A.M., Pereira, J.M., Hassen, G.: Preliminary study on the mechanical behaviour of heat exchanger pile in physical model. Géotechnique 62(11), 1047–1051 (2012). https://doi.org/10.1680/geot.11.T.013
Laloui, L., Nuth, M., Vulliet, L.: Experimental and numerical investigations of the behaviour of a heat exchanger pile. Int. J. Numer. Anal. Meth. Geomech. 30(8), 763–781 (2006). https://doi.org/10.1002/nag.499
McCartney J.S., Rosenberg J.E. (2011) Impact of heat exchange on side shear in thermo-active foundations. In: Geo-Frontiers 2011: advances in geotechnical engineering pp. 488–498. https://doi.org/10.1061/41165(397)51
Ng, C.W.W., Shi, C., Gunawan, A., Laloui, L.: Centrifuge modelling of energy piles subjected to heating and cooling cycles in clay. Geotechnique Lett. 4(4), 310–315 (2014a). https://doi.org/10.1680/geolett.14.00063
Ng, C.W.W., Shi, C., Gunawan, A., Laloui, L., Liu, H.L.: Centrifuge modelling of heating effects on energy pile performance in saturated sand. Can. Geotech. J. 52(8), 1045–1057 (2014b). https://doi.org/10.1139/cgj-2014-0301
Olgun, C.G., Ozudogru, T.Y., Arson, C.F.: Thermo-mechanical radial expansion of heat exchanger piles and possible effects on contact pressures at pile-soil interface. Geotechnique Lett. 4, 170–178 (2014). https://doi.org/10.1680/geolett.14.00018
Wang, B., Bouazza, A., Rao, M.S., Haberfield, C., Barry-Macaulay, D., Baycan, S.: Posttemperature effects on shaft capacity of a full-scale geothermal energy pile. J. Geotechnical, Geoenvironmental Eng. 141(4), 04014125 (2015). https://doi.org/10.1061/(ASCE)GT.1943-5606.0001266
Yavari, N., Tang, A.M., Pereira, J.M., Hassen, G.: Experimental study on the mechanical behaviour of a heat exchanger pile using physical modelling. Acta Geotech. 9(3), 385–398 (2014). https://doi.org/10.1007/s11440-014-0310-7
Acknowledgements
The authors acknowledge the support from the National Natural Science Foundation of China (No. 51778557) and the Qing Lan Project (No. 20160512) by the Jiangsu Province Government.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2019 Springer International Publishing AG, part of Springer Nature
About this paper
Cite this paper
Fei, K., Hong, W., Qian, J. (2019). Numerical Analysis of the Long-Term Performance of Energy Piles in Sand. In: Steyn, W., Holleran, I., Nam, B. (eds) Pavement Materials and Associated Geotechnical Aspects of Civil Infrastructures. GeoChina 2018. Sustainable Civil Infrastructures. Springer, Cham. https://doi.org/10.1007/978-3-319-95759-3_5
Download citation
DOI: https://doi.org/10.1007/978-3-319-95759-3_5
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-95758-6
Online ISBN: 978-3-319-95759-3
eBook Packages: Earth and Environmental ScienceEarth and Environmental Science (R0)