Hydrological Effects of Live Poles on Transient Seepage in an Unsaturated Soil Slope: Centrifuge and Numerical Study
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 143, Issue 3
Abstract
Live poles have been used to stabilize shallow slopes. Most of the existing work has focused on pole reinforcement. The effects of pole transpiration on slope stability are unclear. This study aims to investigate the effects of pole transpiration on rainfall-induced slope hydrology through centrifuge model tests. A novel live-pole modeling technique using real branch cuttings was adopted to simulate the hydrological effects of the transpiration-induced suction in the centrifuge. Suction responses during rainfall were recorded and back-analyzed by seepage analysis. Higher suction was preserved after rainfall when pole transpiration induced higher suction before rainfall. This is because inducing higher suction would lower the soil water storage capacity and hydraulic conductivity. After a rainfall event with a return period of 20 years, up to 10 kPa of suction was preserved in the pole-supported slope to provide stabilization effects.
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Acknowledgments
The authors received a research grant (HKUST6/CRF/12R) from the Research Grants Council of the Government of the Hong Kong SAR and another (2012CB719805) from the Ministry of Science and Technology of the People’s Republic of China under the National Basic Research Program (973 Program). The second author would also like to acknowledge the funding provided by the EU FP7 Marie Curie Career Integration Grant (CIG) under the project BioEPIC Slope, as well as research travel support from the Northern Research Partnership (NRP). The forth author also acknowledge the Hong Kong-Scotland Partners in Post-Doctoral Research (S-HKUST601/15) provided by the Research Grants Council of Hong Kong SAR and the Scottish Government.
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Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 143 • Issue 3 • March 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Sep 20, 2015
Accepted: Jul 19, 2016
Published online: Sep 28, 2016
Discussion open until: Feb 28, 2017
Published in print: Mar 1, 2017
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