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Materials and Structures

, Volume 32, Issue 8, pp 606–610 | Cite as

Wet deposition studies of hydraulic mortars

  • S. Martínez-Ramírez
  • G. E. Thompson
Technical Reports

Abstract

Cement mortars and lime-pozzolan mortars have been exposed to wet/drying cycling of ‘acid rain’ solution, using realistic presentation rates, to simulate outdoor conditions. Cement type, water/cement ratio, and curing temperature were also examined. Form the pH of run-off solution, it is evident that reaction between the mortar and the ‘acid rain’ proceeds over the exposure period, with significant weight increases for the cement mortars and little influence of curing temperature for lime-pozzolan mortars. Exposure of the cement mortar gives to significant calcium loss to run-off and is also associated with retained souuble stalts; these results from the presence of free hydrated lime in the mortar. Conversely, lime-pozzolan mortars, associated with a clacium carbonate compounds, reveal comparatively reduced calcium loss,i.e by about one-tenth that of cement mortar.

Keywords

Silica Fume Acid Rain Soluble Salt Cement Mortar Pozzolanic Reaction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Résumé

Nous avons exposé plusieurs mortiers de ciment et pouzzolane, conservés dans des enceintes climatiques, à des cycles d'humidité et de séchage, à l'action d'une pluie acide, destinée à simuler les conditions extérieures. On a étudié l'influence du type de mortier, du rapport eau/ciment et de la température de la cure. Les valeurs du pH de l'eau de lavage indiquent que la réaction entre le mortier et la pluie acide produite pendant tout le temps d'exposition, est plus grande pour les mortiers de ciment, et que la température à laquelle les mortiers à la chaux ont été conservés a une incidence faible. Dans le cas des mortiers de ciment, on a observé une grande concentration de calcium, dans le liquide résultant du lavage, dû à la présence de chaux libre hydratée dans ces mortiers. À l'inverse, les mortiers à base de chaux et de pouzzolane présentent une perte en chaux de l'ordre du dixième de celle constatée pour les mortiers de ciment.

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References

  1. [1]
    Okochi, H., ‘Deterioration of concrete structure by acid deposition’,Corrosion Engineering 44 (1995) 813–827.Google Scholar
  2. [2]
    Berg Report (Building Effects Review Group), The effects of acid rain deposition on building and building materials in the United Kingdom, (HMSO, London, 1989).Google Scholar
  3. [3]
    Amoroso, G. and Fassina, V., ‘Stone decay and conservation’, 1st Ed., (Elsevier Amsterdam, 1983).Google Scholar
  4. [4]
    Kong, H. L. and Orbison, J. G., ‘Concrete deterioration due to acid precipitation’,ACI Materials Journal 84 (1987) 110–116.Google Scholar
  5. [5]
    Cohen, M. D. and Bentur, A., ‘Durability of Portland cementsilica fume pastes in magnesium sulphate and sodium sulphate solutions’,85 (1988) 148–157.Google Scholar
  6. [6]
    Pavlík, V., ‘Corrosion of hardened cement paste by acetic and nitric acids. Part I: calculation of corrosion depth’,Cement and Concrete Research 24 (3) (1994) 551–562.CrossRefGoogle Scholar
  7. [7]
    Pavlík, V., ‘Corrosion of hardened cement paste by acetic and nitric acids. Part II: Formation and chemical composition of the corrosion products layer’,24 (3) (1994) 1495–1508.CrossRefGoogle Scholar
  8. [8]
    Pavlík, V. and Uncik, S., ‘The rate of corrosion of hardened cement pastes and mortars with additive of silica fume in acids’,27 (11) (1997) 1731–1745.CrossRefGoogle Scholar
  9. [9]
    Martínez-Ramírez, S., Puertas, F., Blanco-Varela, M. T., Thompson, G. E. and Almendros, P., ‘Behaviour of repair lime mortars by wet deposition process’,28 (2) (1998) 221–229.CrossRefGoogle Scholar
  10. [10]
    Martínez-Ramírez, S. and Thompson, G. E., ‘Dry and wet “deposition” studies of the degradation of cement mortars’,Materiales de Construcción 48 (230) (1998) 15–31.CrossRefGoogle Scholar
  11. [11]
    De Belie, N., Debruyckere, M., Nieuwenburd, D. V. and De Blaere, V., ‘Concrete attack by feed acids: accelerated test to compare different concrete compositions and technologies’,ACI Materials Journal 94 (6) (1997) 546–554.Google Scholar
  12. [12]
    Bertorelli, V. and Derwent, R., Air Quality, Department of the Environment, London (1995).Google Scholar
  13. [13]
    Taylor, H. F. W., ‘The Chemistry of Cements’, Vol. II. (Academic Express, London, 1964).Google Scholar

Copyright information

© RILEM 1999

Authors and Affiliations

  • S. Martínez-Ramírez
    • 1
  • G. E. Thompson
    • 1
  1. 1.Corrosion and Protection centre (UMIST)ManchesterUK

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