Reliability-based design optimization strategies based on FORM: a review

Autor(es)

Lopez, Rafael Holdorf ^[1] ; Beck, Andre Teofilo ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Santa Catarina, Dept Civil Engn, BR-88040900 Florianopolis, SC - Brazil

^[2] Univ Sao Paulo, Sao Carlos Sch Engn, Dept Struct Engn, BR-13566590 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Brazilian Society of Mechanical Sciences and Engineering; v. 34, n. 4, p. 506-514, OCT-DEC 2012.
• Citações Web of Science: 31

Resumo

In deterministic optimization, the uncertainties of the structural system (i.e. dimension, model, material, loads, etc) are not explicitly taken into account. Hence, resulting optimal solutions may lead to reduced reliability levels. The objective of reliability based design optimization (RBDO) is to optimize structures guaranteeing that a minimum level of reliability, chosen a priori by the designer, is maintained. Since reliability analysis using the First Order Reliability Method (FORM) is an optimization procedure itself, RBDO (in its classical version) is a double-loop strategy: the reliability analysis (inner loop) and the structural optimization (outer loop). The coupling of these two loops leads to very high computational costs. To reduce the computational burden of RBDO based on FORM, several authors propose decoupling the structural optimization and the reliability analysis. These procedures may be divided in two groups: (i) serial single loop methods and (ii) unilevel methods. The basic idea of serial single loop methods is to decouple the two loops and solve them sequentially, until some convergence criterion is achieved. On the other hand, uni-level methods employ different strategies to obtain a single loop of optimization to solve the RBDO problem. This paper presents a review of such RBDO strategies. A comparison of the performance (computational cost) of the main strategies is presented for several variants of two benchmark problems from the literature and for a structure modeled using the finite element method. (AU)

• Processo FAPESP: 09/12099-6 - Otimização estrutural sob incerteza e risco
• Beneficiário: André Teófilo Beck
• Modalidade de apoio: Auxílio à Pesquisa - Regular