Thermomechanical Behavior of Energy Piles and Interactions within Energy Pile–Raft Foundations
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 146, Issue 9
Abstract
Energy pile groups generally show different behavior than single energy piles because of the presence of rafts and the thermomechanical interaction between piles. This paper presents the results from a series of full-scale field tests to investigate the thermomechanical behavior of an energy pile–raft foundation. The energy pile group was nonsymmetrically operated to analyze the thermally induced group effects. A nonuniform temperature increase may induce a significant change in the distributions of the thermal stress and mobilized shaft resistance. This paper demonstrates that group effects between energy piles can trigger effects in the pile-raft foundation. The nonsymmetrical thermal loading induces a differential displacement in the foundation. When the number of operating piles increases, a lower thermal stress develops along the operating pile and the differential displacement decreases. In addition, because of the indirect heating of the surrounding piles, the differential displacement will continuously decrease during long-term operation, and the thermal stress on the surrounding, nonoperating piles gradually becomes crucial.
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Data Availability Statement
All data, models, and code generated or used during the study appear in the published article.
Acknowledgments
The work presented in this paper was supported by the National Natural Science Foundation of China (Grant Nos. 51778212 and 51922037).
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 146 • Issue 9 • September 2020
Copyright
©2020 American Society of Civil Engineers.
History
Received: Sep 3, 2019
Accepted: Apr 17, 2020
Published online: Jun 25, 2020
Published in print: Sep 1, 2020
Discussion open until: Nov 25, 2020
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