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An Approach to Damage Assessment of Existing Structures.
Yao, J. T. P.
National Science Foundation, Washington, DC. Engineering and Applied Science., October 1979, 32 p.
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Application of fuzzy sets as an alternative and/or supplementary approach to assessing the damage state of existing structures is described. Following occurrence of a hazardous event such as a strong-motion earthquake, voluminous data usually are collected and a simplistic conclusion is issued which transmits scant information to structural engineers concerned with these problems. To correct this situation, the theory of fuzzy sets has been applied to the complex problem of assessing damage to existing structures. Fuzzy sets consist of a mathematical model coupled with provision for the effect of human factors and construction process and experience. For each factor, the gravity of the adverse effect and its consequence are estimated by experts. The report summarizes the state-of-the-art of damage identification of existing structures and presents the fundamental elements of fuzzy sets and their pilot application to actual structural engineering examples. Finally, an approach using fuzzy sets is formulated and discussed in the hope that such a pilot study will stimulate interest in this method among structural engineers. Extensive data, equations and references are included.
Fuzzy sets; Damage assessment; Earthquake engineering; Earthquake resistant structures; Pattern recognition; Set theory; Earthquakes; Structures; Mathematical models; Dynamic structural analysis