000004474 001__ 4474
000004474 005__ 20141118192658.0
000004474 0177_ $$2doi$$a10.3850/978-981-07-2219-7_P109

000004474 0247_ $$210.3850/978-981-07-2219-7_P109
$$adoi
000004474 04107 $$aeng
000004474 046__ $$k2012-05-23
000004474 100__ $$aBeck, André T.
000004474 24500 $$aRobust Optimization of Structural Risks Under Epistemic Uncertainties

000004474 24630 $$n5.$$pProceedings of the 5th Asian-Pacific Symposium on Structural Reliability and its Applications
000004474 260__ $$bResearch Publishing, No:83 Genting Lane, #08-01, Genting Building, 349568 SINGAPORE
000004474 506__ $$arestricted
000004474 520__ $$2eng$$aRisk optimization involves minimization of total expected costs, which include expected costs of failure, evaluated from nominal failure probabilities. Failure probabilities reflect the analyst's degree of belief in the structure's performance, and are said to be nominal because they are evaluated from imperfect and/or incomplete mechanical, mathematical and probabilistic models. Hence, epistemic uncertainties are likely to compromise results of risk optimization. In this paper, the concept of robustness is employed in order to find risk optimization solutions which are less sensitive to epistemic uncertainties. The investigation is based on an elementary but fundamental structural (load-resistance) reliability problem. Intrinsic or aleatoric uncertainties, which can be quantified probabilistically and modeled as random variables, are incorporated in the underlying structural reliability problem. Epistemic uncertainties that can only be quantified possibilistically are modeled as fuzzy variables, based on subjective judgment. Risk optimization is made robust with respect to the whole fuzzy portfolio of epistemic uncertainties. It is shown in the paper that the robust formulation leads to optimal structural configurations which are more conservative, present higher nominal costs but which are less sensitive to epistemic uncertainties, in comparison to the non-robust optimum structures. This is especially true for larger levels of intrinsic uncertainties (in the underlying reliability problem) and for greater costs of failure. An application example, involving optimization of partial safety factors for the codified design of steel beams under bending, is also presented.

000004474 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000004474 653__ $$aStructural reliability, Risk, Robust optimization, Uncertainties, Random variables, Fuzzy variables.

000004474 7112_ $$a5th Asian-Pacific Symposium on Structural Reliability and its Applications$$cSingapore (SG)$$d2012-05-23 / 2012-05-25$$gAPSSRA2012
000004474 720__ $$aBeck, André T.$$iBazán, Felipe A. V.$$iGomes, Wellison J. S.
000004474 8560_ $$ffischerc@itam.cas.cz
000004474 8564_ $$s256474$$uhttps://invenio.itam.cas.cz/record/4474/files/P109.pdf$$yOriginal version of the author's contribution as presented on CD, .
000004474 962__ $$r4180
000004474 980__ $$aPAPER