Documents disponibles écrits par cet auteur

Relating the maximum radial stress on pile shaft to pile base resistance / J. Yang in Géotechnique, Vol. 61 N° 12 (Décembre 2011) 

Public ISBD [article]  in Géotechnique > Vol. 61 N° 12 (Décembre 2011) . - pp. 1087–1092 Titre : Relating the maximum radial stress on pile shaft to pile base resistance Type de document : texte imprimé Auteurs : J. Yang, Auteur ; F. Mu, Auteur Année de publication : 2012 Article en page(s) : pp. 1087–1092 Note générale : Génie Civil Langues : Anglais (eng) Mots-clés : Piles  Bearing  capacity  Sands  stiffness  Compressibility Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : An approximate analytic relationship is developed between the maximum radial stress on the shaft of a displacement pile in sand and the base resistance of the pile. Using the cavity expansion analogy, together with a confined failure mechanism, the ratio between the two quantities, defined as a factor S t, is established as a function of the friction angle, shear stiffness, compressibility and mean effective stress of the sand near the pile tip. It is shown that, given otherwise identical input parameters, the value of S t will decrease with increasing friction angle, and with decreasing mean stress level. It also tends to decrease with an increase in relative density. It is predicted that S t has typical values between 0·03 and 0·05, in broad agreement with the range of empirically derived values in the literature. The relationship also predicts that S t may take much higher values (∼0·1) for piles installed in dense sand or in highly compressible sand. Because of the analytical nature, the established relationship provides useful insights into the mechanisms involved and important implications for design practice. DEWEY : 624.15 ISSN : 0016-8505 En ligne : http://www.icevirtuallibrary.com/content/article/10.1680/geot.10.t.006 [article] Relating the maximum radial stress on pile shaft to pile base resistance [texte imprimé] / J. Yang, Auteur ; F. Mu, Auteur . - 2012 . - pp. 1087–1092. Génie Civil Langues : Anglais (eng) in Géotechnique > Vol. 61 N° 12 (Décembre 2011) . - pp. 1087–1092 Mots-clés : Piles  Bearing  capacity  Sands  stiffness  Compressibility Index. décimale : 624 Constructions du génie civil et du bâtiment. Infrastructures. Ouvrages en terres. Fondations. Tunnels. Ponts et charpentes Résumé : An approximate analytic relationship is developed between the maximum radial stress on the shaft of a displacement pile in sand and the base resistance of the pile. Using the cavity expansion analogy, together with a confined failure mechanism, the ratio between the two quantities, defined as a factor S t, is established as a function of the friction angle, shear stiffness, compressibility and mean effective stress of the sand near the pile tip. It is shown that, given otherwise identical input parameters, the value of S t will decrease with increasing friction angle, and with decreasing mean stress level. It also tends to decrease with an increase in relative density. It is predicted that S t has typical values between 0·03 and 0·05, in broad agreement with the range of empirically derived values in the literature. The relationship also predicts that S t may take much higher values (∼0·1) for piles installed in dense sand or in highly compressible sand. Because of the analytical nature, the established relationship provides useful insights into the mechanisms involved and important implications for design practice. DEWEY : 624.15 ISSN : 0016-8505 En ligne : http://www.icevirtuallibrary.com/content/article/10.1680/geot.10.t.006

Use of state-dependent strength in estimating end bearing capacity of piles in sand / J. Yang in Journal of geotechnical and geoenvironmental engineering, Vol. 134 N°7 (Juillet 2008) 

Public ISBD [article]  in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°7 (Juillet 2008) . - pp. 1010–1014 Titre : Use of state-dependent strength in estimating end bearing capacity of piles in sand Type de document : texte imprimé Auteurs : J. Yang, Auteur ; F. Mu, Auteur Année de publication : 2008 Article en page(s) : pp. 1010–1014 Note générale : Geotechnical and geoenvironmental engineering Langues : Anglais (eng) Mots-clés : Bearing  capacity  Piles  Pile  foundations  Sand  Shear  strength Résumé : The pressure and density dependence of the shear strength of sand poses a tricky problem in pile foundation design. In this study, a correlation is suggested to link the effective friction angle of sand with its initial confining pressure and relative density, and a simple approach incorporating this correlation is presented for predicting pile end bearing capacity. Assessment of the approach against pile load tests shows reasonably good agreement between predictions and measurements. It is also shown that the effect of the state-dependent strength is particularly important in cases where long piles are installed in dense sand deposits and the use of critical state friction angle will produce a conservative prediction in such cases. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A7%2810 [...] [article] Use of state-dependent strength in estimating end bearing capacity of piles in sand [texte imprimé] / J. Yang, Auteur ; F. Mu, Auteur . - 2008 . - pp. 1010–1014. Geotechnical and geoenvironmental engineering Langues : Anglais (eng) in Journal of geotechnical and geoenvironmental engineering > Vol. 134 N°7 (Juillet 2008) . - pp. 1010–1014 Mots-clés : Bearing  capacity  Piles  Pile  foundations  Sand  Shear  strength Résumé : The pressure and density dependence of the shear strength of sand poses a tricky problem in pile foundation design. In this study, a correlation is suggested to link the effective friction angle of sand with its initial confining pressure and relative density, and a simple approach incorporating this correlation is presented for predicting pile end bearing capacity. Assessment of the approach against pile load tests shows reasonably good agreement between predictions and measurements. It is also shown that the effect of the state-dependent strength is particularly important in cases where long piles are installed in dense sand deposits and the use of critical state friction angle will produce a conservative prediction in such cases. En ligne : http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A7%2810 [...]