Department of Plant and Architectural Engineering, Kyonggi University1
Department of Civil and Environmental Engineering, Hannam University2
The current durability design methodology contains deterministic and probabilistic methods. The results vary significantly with changing design parameters and an effect of time. Time effects on diffusion and surface chloride content affect the intruded chloride content, which is directly related with service life and PDF (probability of durability failure). In this work, the time effects on diffusion coefficient and surface chloride content are considered in calculation framework of PDF, and the results of predicted service life from the two different methods are compared considering five design parameters. The effects of cover depth and time-exponent are more dominant than the other parameters, which show 2.38~5.28 and 1.95~4.08 of changing gradient to service life, respectively. Through adopting the effects on probabilistic design method, reasonable service life is obtained with verification that increasing time-exponent through mineral admixture replacement and enhancement of cover depth is very effective on extension of service life.
1. Broomfield, J.P., Corrosion of steel in concrete: understanding, investigation and repair. E&FN, London, (1997), pp. 1-15.
2. Chung, L., Kim, J.H.J. and Yi, S.T., Bond strength prediction for reinforced concrete members with highly corroded reinforcing bars, Cement and concrete composites, (2008), 30 (7), 603-611.
3. Yalciner, H., Eren, O. and Sensoy, S., An experimental study on the bond strength between reinfor-Cement bars and concrete as a function of concrete cover, strength and corrosion level, Cement and Concrete Research, (2012), 42 (5), pp. 643-655.
4. Thomas, M.D.A. and Bentz, E.C., Computer program for predicting the service life and life-cycle costs of reinforced concrete exposed to chlorides, Life365 manual, SFA, (2002), pp. 2-28.
5. CEB Task Group-5.1, 5.2., New approach to durability design, CEB, Sprint-Druck, Stuttgart, (1997), pp. 29-43.
6. RILEM, Durability design of concrete structures, Report of RILEM Technical Committee, 130-CSL, E&FN, (1994), pp. 28-52.
7. Maekawa, K., Ishida, T., and Kishi, T., Multi-scale modeling of concrete performance, Journal of Ad-van-ced Concrete Technology, (2003), 1 (2), pp. 91-126.
8. Song, H.W., Pack, S.W., Lee, C.H., and Kwon, S.J., Service life prediction of concrete structures under marine envi-ronment considering coupled deterioration, Journal of Restoration Building and Monuments, (2006), 12 (4), pp. 265-284.
9. Song, H.W. and Kwon, S.J., Evaluation of chloride penetration in high performance concrete using neural net-work algorithm and micro pore structure, Cement and Concrete Research, (2009), 39 (9), pp. 814-824.
10. Park, S.S., Kwon, S.J., and Jung, S.H., Analysis technique for chloride penetration in cracked concrete using equivalent diffusion and permeation, Construction and Building Materials, (2012), 29 (2), pp. 183-192.
11. Kwon, S.J., Na, U.J., Park, S.S. and Jung, S.H., Service life prediction of concrete wharves with early-aged crack: probabilistic approach for chloride diffusion, Structural Safety, (2009), 31 (1), pp. 75-83.
12. Song, H.W., Pack, S.W., and Ann, K.Y., Probabilistic assessment to predict the time to corrosion of steel in rein-forced concrete tunnel box exposed to sea water, Construction and Building Materials, (2009), 23 (10), pp. 3270-3278.
13. Thomas, M.D.A. and Bamforth, P.B., Modeling chloride diffusion in concrete: effect of fly ash and slag, Cement and Concrete Research, (1999), 29, pp. 487-495.
14. Tang, L. and Joost, G., On the mathematics of time-dependent apparent chloride diffusion coefficient in con-crete, Cement and Concrete Research, (2007), 37, pp. 589-595.
15. Poulsen, E., On a model of chloride ingress into concrete, nordic mini seminar-chloride transport, Depart-ment of Building Materials, Chalmers University of Technology, Gothenburg, 1993.
16. Korea Concrete Institute, Concrete Standard Specification - Durability Part, 2012.
17. EN 1991, Eurocode 1: Basis of Design and Actins on Structures. CEN, 2000.
18. JSCE-Concrete committee., Standard Specification for Concrete Structures, 2012.
19. Japan Society of Civil Engineering, Standard Specifications and Guidelines, 2007.
20. Kwon, S.J. and Park, S.G., Analysis technique for chloride penetration in high performance concrete behavior considering time-dependent accelerated chloride diffusivity, Journal of the Korea Concrete Ins-titute, (2013), 25 (2), pp. 145-153.
21. Kwon, S.J. and Na, U.J., Prediction of durability for RC columns with crack and joint under car-bonation based on probabilistic approach, International Journal of Concrete Structures and Materials, (2011), 5 (1), pp. 11-18.
22. Al-Akhras, N.M. and Smadi, M.M., Properties of tire rubber ash mortar, Cement and Concrete Com-posites, (2004), 26 (7), pp. 821-826.
23. Pettersson, K., Chloride threshold value and corrosion rate in reinforcement concrete, in: Dhir, R. K. and Jones, M. R. (Eds.), Concrete 2000, Vol. 1, E&FN Spon, London UK, (1993), pp. 461-471
24. DuraCrete-Final Technical Report, Probabilistic Performance Based Durability Design of Concrete Structures, Document BE95-1347/R17, European Brite-Euram Ⅲ, Published by CUR, May, The Netherlands, 2000.
25. Thomas, M., Chloride thresholds in marine concrete, Cement and Concrete Research, (1996), 26, pp. 513-519.
26. Ary, C., Buenfeld, N.R., and Newmann, J.B., Factors influencing chloride binding in concrete, Cement and Concrete Research, (1990), 20 (2), pp. 291-300.