Documents disponibles écrits par cet auteur

Response of piles with wings to monotonic and cyclic lateral loading in sand / Britta Bienen in Journal of geotechnical and geoenvironmental engineering, Vol. 138 N° 3 (Mars 2012) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 3 (Mars 2012) . - pp. 364-375 Titre : Response of piles with wings to monotonic and cyclic lateral loading in sand Type de document : texte imprimé Auteurs : Britta Bienen, Auteur ; Jan Dührkop, Auteur ; Jürgen Grabe, Auteur Année de publication : 2012 Article en page(s) : pp. 364-375 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Piles  Lateral  loading  Cyclic  loading  Sand Résumé : Piles are required to withstand large lateral loads compared with the imposed vertical loads in certain applications in the offshore environment, such as for foundations for offshore wind turbines or as anchors for floating facilities. Although typically the soil strength increases with depth, close to the sea bed, the lateral capacity is often low. The requirement to limit pile head deflections necessitates the design of relatively long piles. Increasing the effective pile cross-section through “wings” close to the pile head is shown here with centrifuge model tests to reduce pile head deflections by approximately 50% compared with regular monopiles without “wings” for the same load level. The stiffer initial response of the winged pile also leads to smaller pile head deflections under cyclic loading, although the relative rate of accumulation is similar to that of a monopile. Simple methods for extrapolating from the monotonic pile head deflection to the deflection after thousands of cycles are compared with the results, and are shown to work equally well for piles with and without “wings”. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v138/i3/p364_s1?isAuthorized=no [article] Response of piles with wings to monotonic and cyclic lateral loading in sand [texte imprimé] / Britta Bienen, Auteur ; Jan Dührkop, Auteur ; Jürgen Grabe, Auteur . - 2012 . - pp. 364-375. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 3 (Mars 2012) . - pp. 364-375 Mots-clés : Piles  Lateral  loading  Cyclic  loading  Sand Résumé : Piles are required to withstand large lateral loads compared with the imposed vertical loads in certain applications in the offshore environment, such as for foundations for offshore wind turbines or as anchors for floating facilities. Although typically the soil strength increases with depth, close to the sea bed, the lateral capacity is often low. The requirement to limit pile head deflections necessitates the design of relatively long piles. Increasing the effective pile cross-section through “wings” close to the pile head is shown here with centrifuge model tests to reduce pile head deflections by approximately 50% compared with regular monopiles without “wings” for the same load level. The stiffer initial response of the winged pile also leads to smaller pile head deflections under cyclic loading, although the relative rate of accumulation is similar to that of a monopile. Simple methods for extrapolating from the monotonic pile head deflection to the deflection after thousands of cycles are compared with the results, and are shown to work equally well for piles with and without “wings”. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v138/i3/p364_s1?isAuthorized=no

Undrained bearing capacity of deeply buried flat circular footings under general loading / Youhu Zhang in Journal of geotechnical and geoenvironmental engineering, Vol. 138 N° 3 (Mars 2012) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 3 (Mars 2012) . - pp. 385-397 Titre : Undrained bearing capacity of deeply buried flat circular footings under general loading Type de document : texte imprimé Auteurs : Youhu Zhang, Auteur ; Britta Bienen, Auteur ; Mark J. Cassidy, Auteur Année de publication : 2012 Article en page(s) : pp. 385-397 Note générale : Géotechnique Langues : Anglais (eng) Mots-clés : Footings  Numerical  modeling  Offshore  engineering  Bearing  capacity  Combined  loading  Clays Résumé : Estimation of a footing’s bearing capacity under general loading is a topic of wide interest, especially for the offshore energy industry. Although there have been several studies in the past few decades on shallow footings under general loading, limited work has been done for deeply buried footings. This paper presents results of a numerical investigation into the undrained bearing capacity of deeply buried flat circular footings in clay of both uniform and linearly increasing shear strength profiles. The footings’ uniaxial bearing capacities and failure surfaces under combined vertical, horizontal, and moment loading are reported. The results are analyzed in the context of application by the mobile jack-up industry, for which understanding of the circular spudcan footing’s bearing capacity under general loading is required for site-specific assessments. The paper also presents a parametric study on the effect of a footing’s aspect ratio (thickness/diameter) on its bearing capacity. To conclude, a closed-form expression is proposed to formulate the failure surfaces of the footings under general loading. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v138/i3/p385_s1?isAuthorized=no [article] Undrained bearing capacity of deeply buried flat circular footings under general loading [texte imprimé] / Youhu Zhang, Auteur ; Britta Bienen, Auteur ; Mark J. Cassidy, Auteur . - 2012 . - pp. 385-397. Géotechnique Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 138 N° 3 (Mars 2012) . - pp. 385-397 Mots-clés : Footings  Numerical  modeling  Offshore  engineering  Bearing  capacity  Combined  loading  Clays Résumé : Estimation of a footing’s bearing capacity under general loading is a topic of wide interest, especially for the offshore energy industry. Although there have been several studies in the past few decades on shallow footings under general loading, limited work has been done for deeply buried footings. This paper presents results of a numerical investigation into the undrained bearing capacity of deeply buried flat circular footings in clay of both uniform and linearly increasing shear strength profiles. The footings’ uniaxial bearing capacities and failure surfaces under combined vertical, horizontal, and moment loading are reported. The results are analyzed in the context of application by the mobile jack-up industry, for which understanding of the circular spudcan footing’s bearing capacity under general loading is required for site-specific assessments. The paper also presents a parametric study on the effect of a footing’s aspect ratio (thickness/diameter) on its bearing capacity. To conclude, a closed-form expression is proposed to formulate the failure surfaces of the footings under general loading. DEWEY : 624.1 ISSN : 1090-0241 En ligne : http://ascelibrary.org/gto/resource/1/jggefk/v138/i3/p385_s1?isAuthorized=no