[article]
Titre : |
Nonlinear efficiency of bored pile group under lateral loading |
Type de document : |
texte imprimé |
Auteurs : |
Anne Lemnitzer, Auteur ; Payman Khalili-Tehrani, Auteur ; Eric R. Ahlberg, Auteur |
Année de publication : |
2011 |
Article en page(s) : |
pp. 1673-1685 |
Note générale : |
Géotechnique |
Langues : |
Anglais (eng) |
Mots-clés : |
Pile groups Piers lateral loads Soil-structure interaction |
Index. décimale : |
624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels |
Résumé : |
A 3×3 bored pile group consisting of nine cast-in-drilled-hole reinforced concrete shafts and a comparable single-shaft were subjected to reversed cyclic, lateral head loading to investigate group interaction effects across a wide range of lateral displacements. The piles had the same diameter of d = 0.61 m and similar soil conditions; however, various equipment constraints led to two differences: (1) a fixed head (zero rotation) boundary condition for the single pile versus minor pile cap rotation in the vertical plane for the group and (2) shaft longitudinal reinforcement ratios of 1.8% for the single pile and 1% for the group piles. To enable comparisons between the test results, a calibrated model of the single pile (1.8% reinforcement) was developed and used to simulate the response of a single shaft with 1% reinforcement. Additional simulations of the pile group were performed to evaluate the effects of cap rotation on group response. By comparing the simulated responses for common conditions, i.e., 1% reinforcing ratio and zero head rotation, group efficiencies were found to range from unity at lateral displacements 0.04×d). Hence, we find that group efficiency depends on the level of nonlinearity in the foundation system. The general group efficiency, although not its displacement-dependence, is captured by p-multipliers in the literature for reinforced concrete, fixed-head piles.
|
DEWEY : |
624.1 |
ISSN : |
1090-0241 |
En ligne : |
http://ascelibrary.org/gto/resource/1/jggefk/v136/i12/p1673_s1?isAuthorized=no |
in Journal of geotechnical and geoenvironmental engineering > Vol. 136 N° 12 (Décembre 2010) . - pp. 1673-1685
[article] Nonlinear efficiency of bored pile group under lateral loading [texte imprimé] / Anne Lemnitzer, Auteur ; Payman Khalili-Tehrani, Auteur ; Eric R. Ahlberg, Auteur . - 2011 . - pp. 1673-1685. Géotechnique Langues : Anglais ( eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 136 N° 12 (Décembre 2010) . - pp. 1673-1685
Mots-clés : |
Pile groups Piers lateral loads Soil-structure interaction |
Index. décimale : |
624.1 Infrastructures.Ouvrages en terre. Fondations. Tunnels |
Résumé : |
A 3×3 bored pile group consisting of nine cast-in-drilled-hole reinforced concrete shafts and a comparable single-shaft were subjected to reversed cyclic, lateral head loading to investigate group interaction effects across a wide range of lateral displacements. The piles had the same diameter of d = 0.61 m and similar soil conditions; however, various equipment constraints led to two differences: (1) a fixed head (zero rotation) boundary condition for the single pile versus minor pile cap rotation in the vertical plane for the group and (2) shaft longitudinal reinforcement ratios of 1.8% for the single pile and 1% for the group piles. To enable comparisons between the test results, a calibrated model of the single pile (1.8% reinforcement) was developed and used to simulate the response of a single shaft with 1% reinforcement. Additional simulations of the pile group were performed to evaluate the effects of cap rotation on group response. By comparing the simulated responses for common conditions, i.e., 1% reinforcing ratio and zero head rotation, group efficiencies were found to range from unity at lateral displacements 0.04×d). Hence, we find that group efficiency depends on the level of nonlinearity in the foundation system. The general group efficiency, although not its displacement-dependence, is captured by p-multipliers in the literature for reinforced concrete, fixed-head piles.
|
DEWEY : |
624.1 |
ISSN : |
1090-0241 |
En ligne : |
http://ascelibrary.org/gto/resource/1/jggefk/v136/i12/p1673_s1?isAuthorized=no |
|