Uplift Load-Carrying Capacity of Single and Group Micropiles Installed with Inclined Conditions
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 143, Issue 8
Abstract
In this study, the uplift load-carrying capacity of micropiles was investigated, focusing on the effect of various installation conditions including installation angle (), spacing (), and group configuration. For this purpose, a series of uplift model load tests was conducted using single micropiles (SMP) and group micropiles (GMP). The uplift load capacity of both SMP and GMP increased with up to 30° but decreased for a higher installation angle of . Micropile spacing had less effect on the uplift load capacity for GMP. The uplift load-carrying mechanism of inclined micropiles is proposed based on decomposed axial and lateral loads and resistance components. Based on the proposed load-carrying mechanism, axial and lateral load capacity ratios were proposed and adopted to formulate the uplift load-capacity equation for inclined micropiles. For GMP, the group-effect factor was proposed based on the reduction effect of group micropiles on the overall uplift load capacity. Full-scale uplift load tests were conducted to check the validity of the proposed method. Both SMP and GMP were constructed and tested. It was observed that the estimated results using the proposed method were in good agreement with the measured results.
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Acknowledgments
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (No. 2011-0030040 and NRF-2016R1D1A1A09919098).
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 143 • Issue 8 • August 2017
Copyright
©2017 American Society of Civil Engineers.
History
Received: May 27, 2016
Accepted: Jan 5, 2017
Published ahead of print: Mar 19, 2017
Published online: Mar 20, 2017
Published in print: Aug 1, 2017
Discussion open until: Aug 20, 2017
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