[article]
Titre : |
Coupled-consolidation modeling of a pile in consolidating ground |
Type de document : |
texte imprimé |
Auteurs : |
W. M. Yan, Auteur ; T. K. Sun, Auteur ; L. G. Tham, Auteur |
Année de publication : |
2012 |
Article en page(s) : |
pp. 789–798 |
Note générale : |
Géotechnique |
Langues : |
Anglais (eng) |
Mots-clés : |
Negative skin friction Dragload Pile-soil interface Consolidation |
Résumé : |
When a pile is embedded in a consolidating ground (e.g., newly reclaimed land), soil may settle more than the pile, thus generating negative skin friction along the pile shaft. This negative friction induces additional axial load to the pile (dragload) and pulls the pile further downward (downdrag). In this paper, the problem is investigated numerically with the finite-element package ABAQUS. It was found that the package defaults an interface model that models the mobilized interface strength in a way that the effect of water pressure was overlooked. Therefore, a modified numerical algorithm is proposed in this study. It amends the model by correctly bringing pore water pressure into the calculation steps. which properly simulates the effective stress-dependent nature of the shear strength at the soil-pile interface. The algorithm is then verified by a self-contained simple to understand simulation. A case history of two piles (one of them coated with bitumen) embedded in a consolidating soft ground is then back analyzed with the proposed algorithm. Fully coupled consolidation and geometric nonlinearity are also considered in the analyses. The transient response of the problem is investigated, including the development of dragload, downdrag, and neutral plane with time. The simulation generally fits well with the field measurements. Parametric studies of the effects of pile head loading reveal that the position of the neutral plane depends not only on the magnitude of the applied pile head loading, but is also affected when the load is applied with respect to the consolidation process. |
ISSN : |
1090-0241 |
En ligne : |
http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000651 |
in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 7 (Juillet 2012) . - pp. 789–798
[article] Coupled-consolidation modeling of a pile in consolidating ground [texte imprimé] / W. M. Yan, Auteur ; T. K. Sun, Auteur ; L. G. Tham, Auteur . - 2012 . - pp. 789–798. Géotechnique Langues : Anglais ( eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 7 (Juillet 2012) . - pp. 789–798
Mots-clés : |
Negative skin friction Dragload Pile-soil interface Consolidation |
Résumé : |
When a pile is embedded in a consolidating ground (e.g., newly reclaimed land), soil may settle more than the pile, thus generating negative skin friction along the pile shaft. This negative friction induces additional axial load to the pile (dragload) and pulls the pile further downward (downdrag). In this paper, the problem is investigated numerically with the finite-element package ABAQUS. It was found that the package defaults an interface model that models the mobilized interface strength in a way that the effect of water pressure was overlooked. Therefore, a modified numerical algorithm is proposed in this study. It amends the model by correctly bringing pore water pressure into the calculation steps. which properly simulates the effective stress-dependent nature of the shear strength at the soil-pile interface. The algorithm is then verified by a self-contained simple to understand simulation. A case history of two piles (one of them coated with bitumen) embedded in a consolidating soft ground is then back analyzed with the proposed algorithm. Fully coupled consolidation and geometric nonlinearity are also considered in the analyses. The transient response of the problem is investigated, including the development of dragload, downdrag, and neutral plane with time. The simulation generally fits well with the field measurements. Parametric studies of the effects of pile head loading reveal that the position of the neutral plane depends not only on the magnitude of the applied pile head loading, but is also affected when the load is applied with respect to the consolidation process. |
ISSN : |
1090-0241 |
En ligne : |
http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000651 |
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