Chloride-Enhanced Delayed Ettringite Formation (CLDEF): An Obscure Process

  • S. O. EkoluEmail author
Conference paper
Part of the RILEM Bookseries book series (RILEM, volume 26)


From the historical perspective Delayed Ettringite Formation (DEF) is known to occur usually in cementitious systems made at high cement contents with rapid hardening Portland cements (RHPC) such as Type III cements. Elevated curing temperatures exceeding 70 °C are necessary for DEF to occur. However, there have been controversies, leading to speculations that DEF could occur outside these generally recognized conditions [1, 2, 3, 4, 5, 6, 7, 8, 9]. For example, large pours of concretes under hot weather concreting could increase concrete temperature levels to DEF critical temperatures. Johansen and Thaulow [10] found that a concrete beam of 1 m × 1 m cross-section developed a peak temperature of 84 °C at ambient temperatures of 35 °C, without heat treatment. Hobbs [11] also suggested that large sections of field concretes made with high cement contents of about 500 kg/m3, could attain maximum temperatures in the range of 85 °C. So in hot or tropical climates, concreting conditions similar to those found under heat curing, could arise as a combined effect of the following factors:- use of RHPC/Type III cement, mix designs of high cement contents such as 500 kg/m3, large concrete pours or casting of large sections, and ambient temperatures exceeding 30 °C. In laboratory studies, however, there are no reports of DEF occurrence in the absence of heat curing.


Chloride ingress Delayed ettringite formation Monosulphates Friedel’s salt 


  1. 1.
    Heinz, D., Ludwig, U.: Mechanism of subsequent ettringite formation in mortars and concretes after heat treatment. In: Proceedings of the 8th International Congress on the Chemistry of Cement, Rio de Janeiro, Brasil, vol. V, Theme 4, pp. 189–194, 22–27 September 1986 Google Scholar
  2. 2.
    Heinz, D., Ludwig, U.: Mechanism of secondary ettringite formation in mortars and concretes subjected to heat treatment. In: Scanlon, J.M. (ed.) Concrete Durability, Katharine and Bryant Mather International Conference, SP-100, vol. 2, pp. 2059–2071. American Concrete Institute, Detroit (1987)Google Scholar
  3. 3.
    Heinz, D., Kalde, M., Ludwig, U., Ruediger, I.: Present state of investigation on damaging late ettringite formation (DLEF) in mortars and concretes. In: Erlin, B. (ed.) Ettringite-The Sometimes Host of Destruction, SP-177. ACI Spring Convention, Seattle (1999)Google Scholar
  4. 4.
    Ekolu, S.O.: Heat curing practice in concrete precasting technology - problems and filture directions. J. Concr. Soc. South. Afr. 114, 5–10 (2006)Google Scholar
  5. 5.
    Ekolu, S.O., Thomas, M.D.A., Hooton, R.D.: Dual effectiveness of lithium salt in controlling both delayed ettringite fonnation and ASR in concretes. Cem. Concr. Res. 37(6), 942–947 (2007)CrossRefGoogle Scholar
  6. 6.
    Ekolu, S.O., Thomas, M.D.A., Hooton, R.D.: Implications of pre-formed microcracking in relation to theories of DEF mechanism. Cem. Concr. Res. 37, 161–165 (2007)CrossRefGoogle Scholar
  7. 7.
    Ekolu, S., Rakgosi, G., Hooton, D.: Long-term mitigating effect of lithium nitrate on delayed ettringite fonnatiou and ASR in concrete - microscopic analysis. Mater. Charact. 133, 165–175 (2017)CrossRefGoogle Scholar
  8. 8.
    ASTM C684-99: Standard test method for making, accelerated curing, and testing concrete compression test specimens. ASTM International, West Conshohocken (1999).
  9. 9.
    BS 1881-112: Testing Concrete Part 112: Methods of accelerated curing of test cubes. British Standards Institution (BSI), London, UK (1983)Google Scholar
  10. 10.
    Johansen, V., Thaulow, N.: Heat curing and late formation of ettringite. In: Erlin, B. (ed.) Program on Ettringite-The Sometimes Host of Destruction, ACI SP-177, 1999, pp. 47–64. ACI, Seattle, April 1997Google Scholar
  11. 11.
    Hobbs, D.W.: Expansion and cracking in concrete attributed to delayed ettriugite formation. In: Erlin, B. (ed.) Program on Ettringite-The Sometimes Host of Destruction, AC1 SP-177, 1999, pp. 159–181. ACI Spring Convention, Seattle, April 1997Google Scholar
  12. 12.
    Skalny, J., Odler, I.: The effect of chlorides upon the hydration of Portland cement and upon some clinker minerals. Mag. Concr. Res. 19(61), 203–210 (1967)CrossRefGoogle Scholar
  13. 13.
    Rosenberg, A.M.: Study of the mechanism through which calcium chloride accelerates the set of Portland cement. J. Am. Concr. Inst. Proc. 61, 1261–1269 (1964)Google Scholar
  14. 14.
    Neville, A.M.: Properties of Concrete. 4th edn. Wiley, New York (1996). (also 3rd edition 1981)Google Scholar
  15. 15.
    Midgley, H.G., Illston, J.M.: The penetration of chlorides into hardened cement pastes. Cem. Concr. Res. 14(4), 546–558 (1983)CrossRefGoogle Scholar
  16. 16.
    Zuquan, J., Wei, S., Yunsheng, Z., Jinyang, J., Jianzhong, L.: Interaction between sulfate and chloride solution attack of concretes with and without fly ash. Cem. Concr. Res. 37, 1223–1232 (2007)CrossRefGoogle Scholar
  17. 17.
    Lee, S.T., Park, D.W., Ann, K.Y.: Mitigating effect of chloride ions on sulfate attack of cement mortars with or without silica fume. Can. J. Civ. Eng. 35, 1210–1220 (2008)CrossRefGoogle Scholar
  18. 18.
    Sotiriadis, K., Nikolopoulou, E., Tsivilis, S., Pavlou, A., Chaniotakis, E., Swamy, R.N.: The effect of chlorides on the thaumasite form of sulfate attack of limestone cement concrete containing mineral admixtures at low temperature. Constr. Build. Mater. 43, 156–164 (2013)CrossRefGoogle Scholar
  19. 19.
    Marks, V.J., Dubberke, W.G.: A different perspective for investigation of Portland cement concrete deterioration. Transp. Res. Rec. 1525, 91–96 (1996)CrossRefGoogle Scholar
  20. 20.
    Ekolu, S.O.: Role of heat curing in concrete durability: effects of lithium salts and chloride ingress on delayed ettringite formation, Ph.D. thesis, Civil Engineering Department, University of Taroma, Canada (2004). 217p.Google Scholar
  21. 21.
    Ekolu, S.O., Thomas, M.D.A., Hooton, R.D.: Pessimum effect of externally applied chlorides on expansion due to DEF - proposed mechanism. Cem. Concr. Res. 36, 688–696 (2006)CrossRefGoogle Scholar
  22. 22.
    Matta, Z.G.: Deterioration of concrete structures in the Arabian Gulf. Concr. Int. 33–36 (1993)Google Scholar
  23. 23.
    Ekolu, S.O.: Influence of synthetic zeolite on delayed ettringite formation - preliminary investigation. In: 2nd International Workshop on Durability and Sustainability of Concrete Structures (DSCS), Moscow, Russia, 6–7 June 2018, SP 326-42, pp. 42.1–42.8 (2018)Google Scholar
  24. 24.
    Crammond, N.J.: Examination of mortars containing varying percentages of coarsely crystalline gypsum as aggregate. Cem. Concr. Res. 14, 225–230 (1984)CrossRefGoogle Scholar
  25. 25.
    Xu, A., Shayan, A., Baburamani, P.: Test methods for sulphate resistance of concrete and mechanism of sulphate attack: a state-of-the-art review. ARRB Transport Research Ltd., Review Report 5 (1998). 44 p.Google Scholar
  26. 26.
    ASTM C1556-11a(2016): Standard test method for determining the apparent chloride diffiJsion coefficient of cementitious mixtures by bulk diffusion. ASTMIntematianal, West Conshohocken, PA (2016).
  27. 27.
    Mulongo, L., Ekolu, S.O.: Mathematical modelling of the pessimum action of chlorides on the extent of delayed ettringite formation, Part 1: formulation. Key Eng. Mater. 400–402, 203–208 (2008)CrossRefGoogle Scholar

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© RILEM 2020

Authors and Affiliations

  1. 1.Department of Civil Engineering ScienceUniversity of JohannesburgAuckland ParkSouth Africa

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