STEPWISE OPTIMIZATION OF I-SECTION FLEXIBLE ELEMENTS UNDER A FUZZY APPROACH TO TAKING INTO ACCOUNT CORROSION AND PROTECTIVE PROPERTIES OF ANTICORROSIVE COATING

Author

Mark Fridman, Kryvyi Rih Metallurgical Institute of the National Metallurgical Academy of Ukraine (5, Stephana Tilhy str., Kryvyi Rih, 5006, Ukraine), e-mail: mark17@i.ua, ORCID: 0000-0003-3819-2776

Abstract

This paper is a continuation of research in the field of optimal design of structures under a combined approach to the measurement of corrosion and anticorrosion protective properties of coatings. As noted earlier, such coatings are barrier layers that impede the penetration of aggressive media to the surface of a structure and delay the onset of the process of intense corrosion. In this case, it is important to take into account not only the corrosive effect on the structure, but also be able to estimate the period of time for which the anticorrosive coating loses its protective properties. Since structural elements with damaged protective coatings are able to continue to be subjected to current loads over a considerable period of time, their accelerated corrosion wear is to be taken into account in the damaged areas of coatings. Consequently, the work of the structures protected by coatings consists of two periods: with a protective coating (during which the coating loses protective properties and collapses) and with a damaged protective coating (when there is a severe corrosion wear of unprotected structural areas). The model proposed in the previous study (and implemented on the example of optimization of the flexible elements of a rectangular beam) allows taking into account the smooth transition of the work of structures with protective coatings and the time when the protective properties of anticorrosive coatings practically do not work. This paper considers a solution to a more complicated (due to its multi-extremity) problem of optimization (finding the optimal form) of I-section (double-T) flexible structural elements under a fuzzy approach to taking into account corrosion and anticorrosive coating protective properties.

Keywords: corrosion, anticorrosive coatings, optimization

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References

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Received 05 March 2018

Published 30 September 2018