Evaluation of the Use of Piles as a Stabilizing Element for Slope Stability
Publication: International Journal of Geomechanics
Volume 21, Issue 12
Abstract
This paper assesses the stability of pile reinforced slopes considering the statistical variability of the soil geomechanical parameters and varying the reinforcement geometry. The variation in the factor of safety and the probability of failure of the possibilities under analysis are evaluated with the implementation of reinforcement in different situations. For this purpose, theoretical and numerical methods were used, employing Slide and RSpile programs, which use the limit-equilibrium method to verify slope stability and p–y curves to analyze pile strength. The conclusion is that increasing pile diameter and decreasing the spacing between piles contribute to increase slope stability and the best positioning for piles is close to the slope crest. The factor of safety also increases as pile length increases. However, there is a minimum length for the pile to mobilize stress on the slope and a maximum length beyond which no significant improvements in stability are detected. The displacements in the pile obtained by the p–y curves comply with the admissible recommendations in the literature.
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Acknowledgments
The authors thank the support of the Coordination for the Improvement of Higher Education Personnel (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—CAPES) financing code 001, the Federal University of Uberlândia (UFU) for the acquisition of the software license used in this research.
Notation
The following symbols are used in this paper:
- c
- cohesion;
- ca
- average undrained shear force to the depth z;
- cu
- undrained shear force at depth z;
- D1
- spacing between pile axes;
- D2
- spacing between pile faces;
- d
- pile diameter;
- J
- factor determined experimentally by Matlock that corresponds to 0.5;
- Md
- instability moment;
- MP
- moment caused by the pile;
- MR
- resistant moment;
- z
- depth;
- γ
- unit weight;
- γ′
- effective unit weight of the soil;
- σ
- average stress on the soil;
- τ
- shear stress; and
- ϕ
- friction angle.
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Published In
International Journal of Geomechanics
Volume 21 • Issue 12 • December 2021
Copyright
© 2021 American Society of Civil Engineers.
History
Received: Jan 19, 2021
Accepted: Aug 20, 2021
Published online: Oct 13, 2021
Published in print: Dec 1, 2021
Discussion open until: Mar 13, 2022
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Cited by
- Laura Fantera, Stefania Lirer, Augusto Desideri, Sebastiano Rampello, Efficiency of Piles Stabilizing Slopes in Fine-Grained Soils, International Journal of Geomechanics, 10.1061/(ASCE)GM.1943-5622.0002478, 22, 9, (2022).