Remember Me
Or use your Academic/Social account:


Or use your Academic/Social account:


You have just completed your registration at OpenAire.

Before you can login to the site, you will need to activate your account. An e-mail will be sent to you with the proper instructions.


Please note that this site is currently undergoing Beta testing.
Any new content you create is not guaranteed to be present to the final version of the site upon release.

Thank you for your patience,
OpenAire Dev Team.

Close This Message


Verify Password:
Verify E-mail:
*All Fields Are Required.
Please Verify You Are Human:
fbtwitterlinkedinvimeoflicker grey 14rssslideshare1
O'Flaherty, Fin; Mangat, P. S. (2006)
Languages: English
Types: Article

This paper outlines two procedures for determining the interfacial shrinkage stresses in a repair patch. The first is an analytical approach based on the analogy of a bimetallic strip undergoing contraction (shrinkage). The second is a semi-empirical procedure based on strain monitoring of in situ repairs to in-service bridges. The procedures determine conversion factors to relate the specified properties of the repair materials to their in situ properties in a field repair patch. For example, the shrinkage of a repair patch is influenced by the volume–surface effect, site temperature and relative humidity which are not considered in repair material specification. Creep is initiated in situ by differential shrinkage stresses in the repair material and is determined by adopting an effective elastic modulus approach. Both procedures require the basic material properties (elastic modulus, shrinkage, creep) and geometrical details (width, depth) of the repair patch. The analytical approach incorporates the repair material creep coefficient to predict the interfacial tensile stresses. Alternatively, it uses a less rigorous, elastic approach that omits creep. The creep approach provides higher accuracy whereas the elastic approach overestimates stresses since relaxation by creep is neglected. The elastic approach is recommended for design due to its simplicity and the in-built factor of safety provided by the overestimation of tensile stress. The semi-empirical approach uses an expression derived from long-term field data to determine the strain (and consequently stresses) at the interface of the repair patch and the substrate concrete. The procedures predict the maximum interfacial tensile stress during the service life of a repair patch. They can be used to design crack-free repair patches and optimise repair material selection through a better understanding of the interaction between the repair patch and substrate concrete.

  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

    • 1. Emmons P. H., Vaysburd A. M. and McDonald J. E. Concrete repair in the future turn of the century-any problems? Concrete International, 1994, 16, No. 3, 42-49.
    • 2. Mangat P. S. and O'Flaherty F. J. Factors affecting the efficiency of repair to propped and unpropped bridge beams. Magazine of Concrete Research, 2000, 52, No. 4, 303-319.
    • 3. Mangat P. S. and O'Flaherty F. J. Serviceability characteristics of flowing repairs to propped and unpropped bridge structures. Materials and Structures, 1999, 32, No. 223, 663-672.
    • 4. Mangat P. S. and O'Flaherty, F. J. Influence of elastic modulus on stress redistribution and cracking in repair patches. Cement and Concrete Research, 2000, 30, No. 1, 125-136.
    • 5. Mangat P. S. and O'Flaherty F. J. Long-term performance of high stiffness repairs in highway structures. Magazine of Concrete Research, 1999, 51, No. 5, 325-339.
    • 6. O'Flaherty F. J. and Mangat P. S. Recommendations for the European Prestandard for concrete repair. RILEM 2nd International Workshop on Life Prediction and Aging Management of Concrete Structures, Paris, France, 5-6 May 2003, pp. 237-245.
    • 7. Mangat P. S. and O'Flaherty F. J. Analysis of interfacial shrinkage stress in patch repairs. Magazine of Concrete Research, 2003, 56, No. 7, 375-386.
    • 8. British Standards Institution. BS 1881. Method for determination of static modulus of elasticity in compression, Part 121. BSI, London, 1983.
    • 9. Mangat P. S. and Limbachiya M. K. Repair materials properties which influence long-term performance of concrete structures. Construction and Building Materials, 1995, 9, No. 2, 81-90.
    • 10. Mangat P. S. and Limbachiya M. K. Repair material properties for effective structural application. Cement and Concrete Research, 1997, 27, No. 4, 601-617.
    • 11. Dector M. H. and Lambe R. W. New materials for concrete repair-development and testing. The Indian Concrete Journal, 1993, 67, No. 10, 475-480.
    • 12. Kong F. K. and Evans R. H. Reinforced and Prestressed Concrete, 3rd edn. Van Nostrand Reinhold, New York, 1987.
    • 13. Curing, Cement and Concrete Association of New Zealand. Site Concreting, SC 4 (www.holcim.com/Upload/NZ/ Publications/ECS_Curing%20of%20Concrete.pdf).
    • 14. American Society for Testing Materials. Standard specification for liquid membrane-forming compounds for curing concrete. ASTM C 309-97. ASTM, Philadelphia, PA, USA, 1997.
    • 15. Australian Standard. Liquid membrane-forming compounds for concrete. Standards Australia, Sydney, 1998, AS 3799-1998.
    • 16. Pinelle D. J. Curing stresses in polymer modified repair mortars. Cement, Concrete and Aggregates, CCAGDP, 1995, 17, No. 2, 195-200.
    • 17. Brooks J. J. and Neville A. M. A comparison of creep, elasticity and strength of concrete in tension and in compression. Magazine of Concrete Research, 1978, Vol. 29, No. 100, 131-141.
    • 18. Mosley W. H. and Bungey J. H. Reinforced Concrete Design, 4th edn. McMillan, London, 1990, p. 362.
    • 19. Illston J. M. and Pomeroy C. D. Recommendations for a standard creep test. Concrete, 1975, 9, No. 12, 24-25.
    • 20. Illston J. M. The creep of concrete under uniaxial tension. Magazine of Concrete Research, 1965, 17, No. 51, 77-84.
    • 21. Glanville W. H. and Thomas F. G. Further Investigations on the Creep or Flow of Concrete under Load. Building Research Technical Paper No. 21. HMSO, London, 1939, pp. 5-8.
    • 22. Hanson J. A. A 10-year study of creep properties of concrete. United States Department of the Interior, Bureau of Reclamation, July 1953, Laboratory Report, No. SP-38.
    • 23. Yuan Y. S. and Marosszeky M. Major factors affecting the performance of structural repair. Proceedings of the ACI International Conference on Evaluation and Rehabilitation of Concrete Structures and Innovations in Design. ACI-SP128, Vol. 2. American Concrete Institute, Detroit, 1991, pp. 819-837.
    • 24. Brooks J. J. and Neville A. M. A comparison of creep, elasticity and strength of concrete in tension and in compression. Magazine of Concrete Research, 1977, 29, No. 100, 131-141.
  • No related research data.
  • No similar publications.

Share - Bookmark

Cite this article