Epistemic uncertainty-based reliability analysis for engineering system with hybrid evidence and fuzzy variables

摘要

With the rapid development of reliability analysis theory, the safety assessment for engineering systems with hybrid epistemic uncertainties has received increasing attentions. To overcome the imperfection of traditional single-uncertainty modeling methods, this paper introduces evidence variables and fuzzy variables simultaneously to describe the epistemic uncertain parameters. A novel dual-stage reliability analysis framework is presented, where the first stage incorporates the evidence information by the belief and plausibility measures; the second stage incorporates the fuzzy information by a membership function-like formula. To improve the computational efficiency of response bound prediction associated with various joint focal elements and lambda(k)-cut interval variables, a universal metamodel is constructed by radial basis functions in the global design space. The Latin Hypercube design method without overlapped data is adopted as the sampling strategy. Finally, two numerical examples verify the effectiveness of the proposed method in both mathematical theory and engineering application. (C) 2019 Elsevier B.V. All rights reserved.