Numerical Simulations of Triaxial Tests on Soil-Root Composites and Extension to Practical Problem: Rainfall-Induced Landslide
Publication: International Journal of Geomechanics
Volume 20, Issue 11
Abstract
Root reinforcement is an interesting and environmentally favorable measure for soil stabilization. When properly applied, it can improve soil strength significantly. The paper presents a simulation of a series of drained triaxial tests on soil samples with different levels of root reinforcement in a form of three 5-mm-thick layers, located on different heights. Modified Cam-clay extended for unsaturated soils containing plant roots is used in calculations. The tests are modeled numerically and the results are compared with experimental results from the literature. Missing soil and root parameters are obtained based on the model calibration and further applied in the calculations of the stability of the vegetated slope subjected to rainfall. The influence of the initial root mass in the reinforcing superficial soil layer on the time after which a landslide occurs is investigated. The results suggest that even a minor level of root reinforcement may postpone the development of a rainfall-induced landslide.
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Acknowledgments
Calculations were carried out at the Academic Computer Centre in Gdańsk.
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© 2020 American Society of Civil Engineers.
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Received: Jan 29, 2020
Accepted: Jul 7, 2020
Published online: Sep 2, 2020
Published in print: Nov 1, 2020
Discussion open until: Feb 2, 2021
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