Interpretative Analysis of Lateral Load–Carrying Behavior and Design Model for Inclined Single and Group Micropiles
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 144, Issue 1
Abstract
In this study, the lateral load–carrying capacity of micropiles was investigated focusing on the effect of micropile inclination. A series of model load tests was conducted for both single (SMP) and group (GMP) micropiles with various configuration conditions of inclination angle, load direction, and micropile spacing. To clarify the load-carrying mechanism of inclined micropiles, a finite-element (FE) analysis was performed. The lateral load–carrying capacity of inclined SMPs increased with up to 30° for , whereas opposite trends were observed for . The lateral load–carrying capacity of inclined GMPs increased continuously with owing to the fixity effect with micropile cap. From the results of FE analyses it was found that the main resisting components of inclined micropiles for the lateral load–carrying capacity are the passive failure zone and skin friction mobilized along the micropile surface. Design methods for single and group micropiles subjected to lateral loads were proposed. The values of regression coefficients were evaluated using the results from the model tests and FE analyses. To check the validity of the proposed methods, full-scale field load tests were conducted and used to compare measured and estimated load capacities. Estimated results obtained using the proposed method were in good agreement with measured results.
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Acknowledgments
This work was supported by the Research Institute of Korea Electric Power Corporation. It was also supported by a National Research Foundation of Korea grant funded by the Korean government (MSIP) (2011-0030040 and NRF-2016R1D1A1A09919098).
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 144 • Issue 1 • January 2018
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©2017 American Society of Civil Engineers.
History
Received: Nov 14, 2016
Accepted: Jun 30, 2017
Published online: Nov 15, 2017
Published in print: Jan 1, 2018
Discussion open until: Apr 15, 2018
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