A PRACTICAL METHOD FOR CALCULATING STRUCTURAL RELIABILITY WITH A MIXTURE OF RANDOM AND FUZZY VARIABLES

The objective of this article is to present a practical method for calculating structural reliability in case of a mixture of random and fuzzy input variables. In order to facilitate a unified framework for handling fuzzy and random variables, the novel formulas are proposed for establishing normal random variables equivalent to the symmetric triangular fuzzy number. From these equivalent random ones, the original problem is converted to the basic structural reliability problem, then the methods of the traditional reliability theory should be applied for calculation. Simultaneously, this article presents two notions in terms of central reliability and marginal reliability, and a technique to define them. Numerical results are compared with that of the existing methods, to demonstrate the accuracy and effectiveness of the proposed method.