TAILIEUCHUNG - A formula of evaluating structural safety based on fuzzy set theory

This article presents an approach to assess safety levels of structures. A new formula for determining the fuzzy reliability of structures is proposed for the case where the set of loading effect and set of structural durability are general fuzzy sets. Illustration example concerning the bending strength evaluation of a simple-beam structure, is presented with the choice of triangular fuzzy sets for loading effect and structural durability. | Vietnam Journal of Mechanics, VAST, Vol. 33, No. 3 (2011), pp. 162 – 169 A FORMULA OF EVALUATING STRUCTURAL SAFETY BASED ON FUZZY SET THEORY Le Xuan Huynh, Le Cong Duy National University of Civil Engineering, Vietnam Abstract. This article presents an approach to assess safety levels of structures. A new formula for determining the fuzzy reliability of structures is proposed for the case where the set of loading effect and set of structural durability are general fuzzy sets. Illustration example concerning the bending strength evaluation of a simple-beam structure, is presented with the choice of triangular fuzzy sets for loading effect and structural durability. Key words: Fuzzy logic and application, fuzzy reliability. 1. INTRODUCTION Data and models encountered in natural sciences and engineering are more or less characterized by uncertainty. The uncertainty models can be investigated by the fuzzy theory. Fuzzy theory has been known since 1965. Professor Lofti A. Zadeh had the first article presenting the fuzzy sets and fuzzy logic. It is firstly applied in electronic engineering, next in fields of computer sciences and control techniques. And since 1970, fuzzy set theory has been applied and developed to the fields of civil engineering and computational mechanics. In order to assess the safety of construction structures based on fuzzy models, now, there are two trends for approaching. The first trend, based on fuzzy probability theory is to establish methods to define the fuzzy reliability of structures [1]. Using the second trend, researchers propose different formulas to calculate the fuzzy reliability based on fuzzy set theory and random interference model [2-7]. This article presents a new formula to define the fuzzy reliability following the second trend. Numerical examples are compared with some formulas for estimating the safety of structures. In [2], we present a formula to evaluate safety levels and/or failure levels of structures, in cases where .

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• Evaluating structural safety based on fuzzy set theory
• Evaluating structural safety
• The fuzzy reliability
• Simple beam structure
• Dang Dinh Ang
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