Lateral Load Behavior of Inclined Micropiles Installed in Soil and Rock Layers
Publication: International Journal of Geomechanics
Volume 21, Issue 6
Abstract
In this paper, the lateral load-carrying behavior of inclined micropiles installed in various soil–rock layer conditions was investigated based on the results from the model load tests and finite-element analyses. The effects of micropile inclination angle, load direction, and rock-embedded ratio were considered in the study. Improved load-carrying behavior was obtained from negatively inclined micropiles in rock with the load direction of 0°, whereas it was disadvantageous for the load directions of 90° and 180°. The lateral load capacity of micropiles for the mixed layer condition increased with a rock-embedded ratio and became larger at a higher inclination angle. Marked increases in the lateral load capacity were observed for rock-embedded ratios larger than 0.8, below which the increases were moderate. The inclination and rock-embedded conditions of micropiles were both adequate to enhance the lateral load-carrying behavior of micropiles, whereas the effect of the rock-embedded condition was less beneficial unless largely embedded. It was also indicated that the maximum benefit of micropiles embedded in rock could be achieved by further reinforcing the stiffness in the upper part of micropiles within the soil layer. It was confirmed that the previously proposed method to estimate the lateral load capacity of inclined micropiles in the sand could be effectively used for the case in rock and the mixed soil–rock layer condition for practical purposes.
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Acknowledgments
This work was supported by Korea Agency for Infrastructure Technology Advancement (KAIA), Korea Institute of Energy Technology Evaluation and Planning (KETEP), the Ministry of Trade, Industry & Energy (MOTIE), and the National Research Foundation of Korea (NRF) (Nos. 20SMIP-A158708-01, 20194030202460, and 2020R1A2C2011966).
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Published In
International Journal of Geomechanics
Volume 21 • Issue 6 • June 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: May 13, 2020
Accepted: Jan 4, 2021
Published online: Mar 24, 2021
Published in print: Jun 1, 2021
Discussion open until: Aug 24, 2021
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