[article] 
inJournal of geotechnical and geoenvironmental engineering > Vol. 137 N° 12 (Décembre 2011) . - pp. 1211- 1221

Titre :	Reliability-based optimization of geotechnical systems
Type de document :	texte imprimé
Auteurs :	J. Zhang, Auteur ; J.-M. Zhang, Auteur ; Wilson H. Tang, Auteur
Année de publication :	2012
Article en page(s) :	pp. 1211- 1221
Note générale :	Géotechnique
Langues :	Anglais (eng)
Mots-clés :	Reliability Optimization Shallow foundation Retaining wall Probabilistic method
Résumé :	Reliability-based optimization (RBO) intends to minimize the cost involved in a design while satisfying all technical requirements specified by using reliability theory. Although this idea is attractive, its implementation is generally difficult because an accurate evaluation of the reliability constraints is often computationally prohibitive when it is coupled with the minimization of a cost function. This paper suggests an indirect method for RBO of geotechnical systems initially on the basis of the mean first-order reliability method (MFORM). Because reliability analysis with MFORM is very efficient, the computational work involved in RBO is greatly reduced. The major concern about MFORM is that it is not an accurate reliability method. A reliability index mapping function was used to relate the reliability index calculated by MFORM to that calculated by a more accurate method. When the mapping function perfectly reflects the relationship between MFORM reliability index and that from an accurate reliability method, the RBO from MFORM and the original RBO problem are equivalent. When a perfect mapping function cannot be built, a procedure has been suggested to fine-tune the optimal design such that accurate reliability constraints can be maintained in the final optimal design. The proposed method is illustrated with two geotechnical examples: the optimal design of a shallow foundation and a gravity retaining wall.
DEWEY :	624.1
ISSN :	1090-0241
En ligne :	http://ascelibrary.org/gto/resource/1/jggefk/v137/i12/p1211_s1?isAuthorized=no

[article] Reliability-based optimization of geotechnical systems [texte imprimé] / J. Zhang, Auteur ; J.-M. Zhang, Auteur ; Wilson H. Tang, Auteur . - 2012 . - pp. 1211- 1221.
Géotechnique
Langues : Anglais (eng)
in Journal of geotechnical and geoenvironmental engineering > Vol. 137 N° 12 (Décembre 2011) . - pp. 1211- 1221

Mots-clés :	Reliability Optimization Shallow foundation Retaining wall Probabilistic method
Résumé :	Reliability-based optimization (RBO) intends to minimize the cost involved in a design while satisfying all technical requirements specified by using reliability theory. Although this idea is attractive, its implementation is generally difficult because an accurate evaluation of the reliability constraints is often computationally prohibitive when it is coupled with the minimization of a cost function. This paper suggests an indirect method for RBO of geotechnical systems initially on the basis of the mean first-order reliability method (MFORM). Because reliability analysis with MFORM is very efficient, the computational work involved in RBO is greatly reduced. The major concern about MFORM is that it is not an accurate reliability method. A reliability index mapping function was used to relate the reliability index calculated by MFORM to that calculated by a more accurate method. When the mapping function perfectly reflects the relationship between MFORM reliability index and that from an accurate reliability method, the RBO from MFORM and the original RBO problem are equivalent. When a perfect mapping function cannot be built, a procedure has been suggested to fine-tune the optimal design such that accurate reliability constraints can be maintained in the final optimal design. The proposed method is illustrated with two geotechnical examples: the optimal design of a shallow foundation and a gravity retaining wall.
DEWEY :	624.1
ISSN :	1090-0241
En ligne :	http://ascelibrary.org/gto/resource/1/jggefk/v137/i12/p1211_s1?isAuthorized=no