Improved Performance of Monopiles When Combined with Footings for Tower Foundations in Sand
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 140, Issue 7
Abstract
This paper presents the results from a series of centrifuge tests and three-dimensional finite-element (FE) analyses, which examined the benefits of combining a footing with a monopile as a solution for foundations that are subjected to large moment loading, such as those used for towers and wind turbines. The experiments were carried out in silica sand and involved monotonic application of lateral loads at an equivalent prototype height of 26 m above the foundations. Tests were conducted on piled footings, monopiles, and unpiled footings. These experimental results together with the findings from the FE analyses show that the footing interacts positively with the piled foundation and that both the rotational stiffness and capacity of the combined piled footing system are greater than the sum of the individual contributions. Increased capacity arises as the footing causes a significant reduction in moment loading on the pile (hence facilitating the application of larger loads), primarily owing to an increased footing effective area arising from the tension capacity of the pile.
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Acknowledgments
The authors acknowledge the funding provided by the Australian Research Council and are grateful for the assistance provided by Don Herley, the beam centrifuge technician at UWA. The authors also acknowledge the contributions of Sarah Harloe and Jiaoxiang Li, who worked on this research as part of their undergraduate thesis studies at UWA.
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 140 • Issue 7 • July 2014
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Apr 10, 2013
Accepted: Feb 6, 2014
Published online: Mar 20, 2014
Published in print: Jul 1, 2014
Discussion open until: Aug 20, 2014
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