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Fuzzy inference based cover thickness estimation of reinforced concrete structure quantitatively considering salty environment impact

  • Do, Jeong-Yun (Research Center of Industrial Technology, Chonbuk National University)
  • Received : 2006.03.13
  • Accepted : 2006.06.20
  • Published : 2006.04.01

Abstract

This article involves architecting prototype-fuzzy expert system for designing the nominal cover thickness by means of fuzzy inference for quantitatively representing the environment affecting factor to reinforced concrete in chloride-induced corrosion environment. In this work, nominal cover thickness to reinforcement in concrete was determined by the sum of minimum cover thickness and tolerance to that defined from skill level, constructability and the significance of member. Several variables defining the quality of concrete and environment affecting factor (EAF) including relative humidity, temperature, cyclic wet and dry, and the distance from coast were treated as fuzzy variables. To qualify EAF the environment conditions of cycle degree of wet-dry, relative humidity, distance from coast and temperature were used as input variables. To determine the nominal cover thickness a qualified EAF, concrete grade, and watercement ratio were used. The membership functions of each fuzzy variable were generated from the engineering knowledge and intuition based on some references as well as some international codes of practice.

Keywords

References

  1. ACI Committee 116 (2004), 'Cement and concrete terminology', American Concrete Institute, pp. 25
  2. ACI Committee 201 (2004), 'Guide to durable concrete, manual of concrete practice', American Concrete Institute, 16-20
  3. Bentur, A., et al. (1997), Steel Corrosion in Concrete; Fundamentals and Civil Engineering Practice, E & FN Spon, London, pp.24-58 and 146-155
  4. British Standard 8110 (1985), 'Structural Use of Concrete, Part 1, Code of Practice for Design and Construction', British Standard Institute
  5. Broomfield, J.P. (1992), Corrosion of Steel in Concrete, E&F.N. Spoon, London
  6. BS EN 206-1/BS 8500 (2002), 'Guide to the selection of concrete quality and cover to reinforcement for normal concrete structures', British Cement Association, Berkshire, 1-3
  7. CEB (1989), 'Durable concrete structures', CEB Design Guide, Bulletin d'information 182
  8. Do, Jeongyun (2005), 'Fuzzy theory-based performance design for durability of RC structures and strategy for its repair/retrofit', Doctoral dissertation in Chonbuk National University
  9. Do, Jeongyun (2004) 'Nominal cover thickness design of RC quantitatively considering environment condition by means of fuzzy inference system', Journal of Asian Architecture and Building Engineering, 3(2), 225-232 https://doi.org/10.3130/jaabe.3.225
  10. ENV 13670-1 (2000), Execution of Concrete Structures, European Committee for Standardization
  11. Klir, George J. and Yuan, Bo (1995), 'Fuzzy sets and fuzzy logic: Theory and applications', Prentice-Hall Inc., USA, 97-117
  12. Maher, A. B. (2003), 'Performance of concrete in a coastal environment', Cement Conc. Compo., 25(6), 539-548 https://doi.org/10.1016/S0958-9465(02)00093-8
  13. Mun, K.I. and Lee, H.Y. (2003), 'Intellectual information system using Matlab', Ajin company, Seoul (In Korean), pp.12-32
  14. Morinaga, S. (1991), 'Prediction of service lives of reinforced concrete buildings based on the corrosion rate of reinforcing steel, durability of building materials and components', Proc of the 5th Int. Conf., Brighton, E.&F.N. Spoon, London, pp.5-16
  15. Oh, Byounghwan, et al (2004), 'Chloride diffusion and corrosion initiation time of reinforced concrete structures', Proceedings of the International Workshop on Microstructure and Durability to Predict Service Life of Concrete Structures, Sapporo, Japan
  16. Papadakis, V. G., Fardis, M. N. and Vayenas, C. G. (1991), 'Fundamental concrete carbonation model and application to durability of reinforced concrete, durability of building materials and components', Proc. of Int. Conf., Brighton, Eds. J. M. Baker. P. J. Nixon, A. J. Majumdar, H. Davies E. & F. N. Spoon, London, pp.27-38
  17. prEN 1992-1-1 (2002), 'Eurocode 2: design of concrete structures - Part 1: General rules and rules for buildings', European Committee for Standardization
  18. Roper, H. and Bajewa, D. (1991), 'Durability of concrete'. The 2nd. Int. Conf., ed. V.M Malhotra, Detroit, Michigan, American Concrete Institute
  19. Somerville, G. (2001), The Design Life of Structures, Thomson Litho Ltd., East Kilbride, Scotland, 1992, pp.25-39
  20. Yoshiki, T., et al. (2001), 'Study on required cover depth of concrete highway bridges in coastal environment,' 17th U.S.-Japapn Bridge Engineering Workshop, Tsukuba, Japan, 1-16
  21. Zivica, V. (1995), 'The rate of corrosion of concrete reinforcement and possibilities of its mathematical modelling', Bulletin of Material Science, 18(2), 115-124 https://doi.org/10.1007/BF02747530
  22. Zivica, V. (1994a), 'Mathematical modelling of concrete reinforcement corrosion rate and the possibility of service life prediction of reinforced concrete. I. Influence of environmental relative humidity and time', Building Research J., 42(3), 85-198
  23. Zivica, V. (1994b), 'Mathematical modelling of concrete reinforcement corrosion rate and the possibility of service life prediction of reinforced concrete. II. Influence of chloride concentration in reinforced concrete', Building Research J., 42(3), 199-205
  24. Zivica, V. (1998), 'Experimental principles in the research of chemical resistance of cement based materials', Constr. Build. Mat., 12, 365-371 https://doi.org/10.1016/S0950-0618(98)00018-X
  25. Zivica, V. (2003a), 'Corrosion of reinforcement induced by environment containing chloride and carbon dioxide', Bulletin of Material Science, 26(6), 605-608 https://doi.org/10.1007/BF02704323
  26. Zivica, V. (2003b), 'Influence of w/c ratio on rate of chloride induced corrosion of steel reinforcement and its dependence on ambient temperature', Bulletin of Material Science, 26(5), 471-475 https://doi.org/10.1007/BF02707343

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