Compressive Load-Carrying Behavior of Inclined Micropiles Installed in Soil and Rock Layers
Publication: International Journal of Geomechanics
Volume 20, Issue 9
Abstract
Micropiles are an effective option to enhance the load-carrying performance of buildings and infrastructure. In this study, the compressive load capacity and load-carrying mechanism of inclined micropiles in soil and rock layers were investigated experimentally and analytically. A series of model load tests was conducted using model micropiles and rock specimens. The finite element analyses were performed for inclined micropiles in various soil-rock layer configurations. Vertical micropiles in rock exhibited the highest load-carrying capacity whereas inclined conditions were not beneficial. For the rock-mounted condition, the base capacity dominated the total load capacity when the inclination was lower than 15°. For partially and fully rock-embedded conditions, the main load-carrying component was the skin friction and virtually no load was transferred to the micropile base. Micropile inclination caused less mobilization of skin friction within the rock-embedded zone. Instead, the passive resistance within the upper sand layer dominated the overall load capacity, which explained decreasing load capacity with increasing inclination for a rock-embedded condition.
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Acknowledgments
This work was supported by the Basic Science Research Program through the Korea Institute of Energy Technology Evaluation and Planning (KETEP), the Ministry of Trade, Industry and Energy (MOTIE), the National Research Foundation of Korea (NRF), and Korea Agency for Infrastructure Technology Advancement (KAIA) with grants funded by the Government of Korea (Nos. 20194030202460, 2020R1A2C201196611, and 1615011670).
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Published In
International Journal of Geomechanics
Volume 20 • Issue 9 • September 2020
Copyright
© 2020 American Society of Civil Engineers.
History
Received: Feb 14, 2019
Accepted: Mar 24, 2020
Published online: Jun 17, 2020
Published in print: Sep 1, 2020
Discussion open until: Nov 17, 2020
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