[article] 
inJournal of geotechnical and geoenvironmental engineering > Vol. 134 n°11 (Novembre 2008) . - pp. 1587–1594

Titre :	Reliability index for serviceability limit state of building foundations
Type de document :	texte imprimé
Auteurs :	Yu Wang, Auteur ; Fred H. Kulhawy, Auteur
Année de publication :	2009
Article en page(s) :	pp. 1587–1594
Note générale :	Geotechnical and geoenvironmental engineering
Langues :	Anglais (eng)
Mots-clés :	Reliability Serviceability Limit states foundations Cast in place Piles
Résumé :	Extensive research has been conducted on reliability-based design (RBD) for the ultimate limit state (ULS). Several RBD codes have been developed and implemented around the world that calibrate the ULS design for a target ULS reliability index (βuls) . However, the serviceability limit-state (SLS) design still is considered using conventional deterministic approaches with an unknown SLS reliability index (βsls) . This paper presents a relationship between βsls and the βuls that is specified already in the RBD codes. This relationship is linear, and a key variable in it is the ratio (R) of the SLS capacity (Qsls) to the ULS capacity (Quls) . Both closed-form approximations and Monte Carlo simulations are used to characterize R probabilistically. For illustration, the relationship then is used to estimate βsls for augered cast-in-place piles designed in accordance with the RBD methodologies in the National Building Code of Canada. The results are highly dependent on the statistics of the limiting tolerable foundation settlement (ylt) . For larger ylt values, the calculated βsls>βuls , which means that ULS designs automatically satisfy SLS criteria. For smaller ylt values, SLS criteria begin to control the design. The importance of sound ylt criteria is stressed.
En ligne :	http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A11%281 [...]

[article] Reliability index for serviceability limit state of building foundations [texte imprimé] / Yu Wang, Auteur ; Fred H. Kulhawy, Auteur . - 2009 . - pp. 1587–1594.
Geotechnical and geoenvironmental engineering
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 134 n°11 (Novembre 2008) . - pp. 1587–1594

Mots-clés :	Reliability Serviceability Limit states foundations Cast in place Piles
Résumé :	Extensive research has been conducted on reliability-based design (RBD) for the ultimate limit state (ULS). Several RBD codes have been developed and implemented around the world that calibrate the ULS design for a target ULS reliability index (βuls) . However, the serviceability limit-state (SLS) design still is considered using conventional deterministic approaches with an unknown SLS reliability index (βsls) . This paper presents a relationship between βsls and the βuls that is specified already in the RBD codes. This relationship is linear, and a key variable in it is the ratio (R) of the SLS capacity (Qsls) to the ULS capacity (Quls) . Both closed-form approximations and Monte Carlo simulations are used to characterize R probabilistically. For illustration, the relationship then is used to estimate βsls for augered cast-in-place piles designed in accordance with the RBD methodologies in the National Building Code of Canada. The results are highly dependent on the statistics of the limiting tolerable foundation settlement (ylt) . For larger ylt values, the calculated βsls>βuls , which means that ULS designs automatically satisfy SLS criteria. For smaller ylt values, SLS criteria begin to control the design. The importance of sound ylt criteria is stressed.
En ligne :	http://ascelibrary.org/doi/abs/10.1061/%28ASCE%291090-0241%282008%29134%3A11%281 [...]