Investigation on the Effects of Increasing in Wetting/Drying Cycles on Chloride Ingress into Unsaturated Concrete: A Simulation of Splash Condition

Document Type : Original Article

Authors

1 Faculty member Concrete Technology Department; Road, Housing & Urban Development Research Center (BHRC)

2 MSc in Civil Engineering, Structural Engineering from Islamic Azad University (Qazvin Branch)

3 Faculty member of Road, Housing and Urban Development Research Center (BHRC)

4 Faculty Member of Road, Housing and Urban Development Research Center (BHRC)

Abstract

The chloride ingress into concrete and corrosion of steel reinforcement due to wetting/drying (WD) cycles is a main issue caused to decline the service life of reinforced concrete structures. In this paper, the effects of WD cycles on chloride penetration in concrete were studied using a finite element based numerical model. The results showed that the chloride ingress into concrete increased with increasing in daily WD cycles. The chloride concentration after 10 years at depth of 50 mm and the maximum chloride concentration of the submerged specimen were 2.4 and 2.0 times lower than the specimen exposed to 2 and 24 WD cycles, respectively. These ratios increased up to 4.2 and 3.7 when the WD cycle increased to 24 cycles. The numerical model outputs also indicated that the chloride concentration at depth of 50 mm and the maximum chloride closely tended up to a constant amount by increasing the number of WD cycle up to 100 cycles (similar to splash condition).

Keywords

References

 
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Journal of Concrete Structures and Materials
Volume 3, Issue 2 - Serial Number 6
December 2018
Pages 65-76

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History

  • Receive Date: 04 August 2018
  • Revise Date: 27 October 2018
  • Accept Date: 13 January 2019

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