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Loss in anchor embedment during plate anchor keying in clay / Zhenhe Song in Journal of geotechnical and geoenvironmental engineering, Vol. 135 N° 10 (Octobre 2009) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 135 N° 10 (Octobre 2009) . - pp. 1475–1485 Titre : Loss in anchor embedment during plate anchor keying in clay Type de document : texte imprimé Auteurs : Zhenhe Song, Auteur ; Yuxia Hu, Auteur ; Conleth O’Loughlin, Auteur Année de publication : 2009 Article en page(s) : pp. 1475–1485 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : AnchorsClaysCentrifuge  modelsDeformationFinite  element  methodImaging  techniquesRotation Résumé : Vertically installed plate anchors have been investigated in this paper by numerical analysis and centrifuge modeling. In the numerical analysis, the large deformation finite-element method (remeshing and interpolation technique with small strain) was used to simulate strip plate anchor rotation. In the centrifuge model tests, transparent soils were used to observe square anchor rotation. The loss in anchor embedment during anchor keying was assessed for anchors in uniform and normally consolidated soils with anchor pullout angle varying from 30° to 90° to the horizontal. It was found that the loss in anchor embedment during anchor keying may be expressed in terms of a nondimensional anchor geometry factor, which is a function of the eccentricity of the padeye, angle of loading, and the net moment applied to the anchor at the stage where the applied load balances the anchor weight. However, once the anchor geometry factor reaches a certain value, the loss in anchor embedment stabilizes at 0.25–0.5 times the anchor width. The loss in anchor embedment decreases linearly with decreasing pullout angle. Simple formulae and design procedures have been proposed to estimate the loss in anchor embedment during keying. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000098 [article] Loss in anchor embedment during plate anchor keying in clay [texte imprimé] / Zhenhe Song, Auteur ; Yuxia Hu, Auteur ; Conleth O’Loughlin, Auteur . - 2009 . - pp. 1475–1485. Geotechnical and geoenvironmental engineering Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 135 N° 10 (Octobre 2009) . - pp. 1475–1485 Mots-clés : AnchorsClaysCentrifuge  modelsDeformationFinite  element  methodImaging  techniquesRotation Résumé : Vertically installed plate anchors have been investigated in this paper by numerical analysis and centrifuge modeling. In the numerical analysis, the large deformation finite-element method (remeshing and interpolation technique with small strain) was used to simulate strip plate anchor rotation. In the centrifuge model tests, transparent soils were used to observe square anchor rotation. The loss in anchor embedment during anchor keying was assessed for anchors in uniform and normally consolidated soils with anchor pullout angle varying from 30° to 90° to the horizontal. It was found that the loss in anchor embedment during anchor keying may be expressed in terms of a nondimensional anchor geometry factor, which is a function of the eccentricity of the padeye, angle of loading, and the net moment applied to the anchor at the stage where the applied load balances the anchor weight. However, once the anchor geometry factor reaches a certain value, the loss in anchor embedment stabilizes at 0.25–0.5 times the anchor width. The loss in anchor embedment decreases linearly with decreasing pullout angle. Simple formulae and design procedures have been proposed to estimate the loss in anchor embedment during keying. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%29GT.1943-5606.0000098

Numerical simulation of vertical pullout of plate anchors in clay / Zhenhe Song in Journal of geotechnical and geoenvironmental engineering, Vol. 134 N° 6 (Juin 2008) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N° 6 (Juin 2008) . - pp. 866-875 Titre : Numerical simulation of vertical pullout of plate anchors in clay Type de document : texte imprimé Auteurs : Zhenhe Song, Auteur ; Yuxia Hu, Auteur ; Mark F. Randolph, Auteur Année de publication : 2010 Article en page(s) : pp. 866-875 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Anchors  Pull  out  resistance  Soil  strength  Deep  water  Finite  element  method  Deformation Résumé : The behavior of strip and circular plate anchors during vertical pullout in uniform and normally consolidated clays was studied in this paper by means of small strain and large deformation finite-element analyses. Both fully bonded (attached), and “vented” (no suction on rear face), anchors were considered. The current numerical results were compared with existing laboratory test data, finite-element results, and analytical solutions. This study showed that, in small strain analysis, the scatter of existing data was mainly due to the effect of soil stiffness. In large deformation analysis, when soil and anchor base were attached with suction, the pullout capacity factor formed a unique curve independent of the soil strength (su) , soil effective unit weight (γ′) and anchor size ( B =width of strip anchor and D =diameter of circular anchor). The transitional embedment depth ratio, HSD∕B or HSD∕D , (where HSD =transition depth between shallow and deep embedment) was 1.4 for a strip anchor and 0.75 for a circular anchor. The ultimate pullout capacity factors (Nc) for deep embedment were 11.6 and 11.7 for smooth and rough strip anchors and 13.1 and 13.7 for smooth and rough circular anchors, respectively. However, when the anchor base was vented, the soil stayed attached to the anchor base for deep embedment, and the pullout capacity was therefore the same as for the attached anchor. The separation depth ratio, Hs∕B or Hs∕D , (where Hs =embedment depth at which the soil and anchor base separated) was found to increase linearly with the normalized strength ratio, su/γ′B or su / γ′D . En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A6%2886 [...] [article] Numerical simulation of vertical pullout of plate anchors in clay [texte imprimé] / Zhenhe Song, Auteur ; Yuxia Hu, Auteur ; Mark F. Randolph, Auteur . - 2010 . - pp. 866-875. Geotechnical and geoenvironmental engineering Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N° 6 (Juin 2008) . - pp. 866-875 Mots-clés : Anchors  Pull  out  resistance  Soil  strength  Deep  water  Finite  element  method  Deformation Résumé : The behavior of strip and circular plate anchors during vertical pullout in uniform and normally consolidated clays was studied in this paper by means of small strain and large deformation finite-element analyses. Both fully bonded (attached), and “vented” (no suction on rear face), anchors were considered. The current numerical results were compared with existing laboratory test data, finite-element results, and analytical solutions. This study showed that, in small strain analysis, the scatter of existing data was mainly due to the effect of soil stiffness. In large deformation analysis, when soil and anchor base were attached with suction, the pullout capacity factor formed a unique curve independent of the soil strength (su) , soil effective unit weight (γ′) and anchor size ( B =width of strip anchor and D =diameter of circular anchor). The transitional embedment depth ratio, HSD∕B or HSD∕D , (where HSD =transition depth between shallow and deep embedment) was 1.4 for a strip anchor and 0.75 for a circular anchor. The ultimate pullout capacity factors (Nc) for deep embedment were 11.6 and 11.7 for smooth and rough strip anchors and 13.1 and 13.7 for smooth and rough circular anchors, respectively. However, when the anchor base was vented, the soil stayed attached to the anchor base for deep embedment, and the pullout capacity was therefore the same as for the attached anchor. The separation depth ratio, Hs∕B or Hs∕D , (where Hs =embedment depth at which the soil and anchor base separated) was found to increase linearly with the normalized strength ratio, su/γ′B or su / γ′D . En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A6%2886 [...]