HU Yuquan,HU Shaowei,LI Wenhao,et al.Influence and Comparative Analysis of Curing Conditions on Chloride Resistance of BCCP[J].Journal of Disaster Prevention and Mitigation Engineering,2023,43(03):559-567.
HU Yuquan,HU Shaowei,LI Wenhao,et al.Influence and Comparative Analysis of Curing Conditions on Chloride Resistance of BCCP[J].Journal of Disaster Prevention and Mitigation Engineering,2023,43(03):559-567. DOI: 10.13409/j.cnki.jdpme.20210707003.
Influence and Comparative Analysis of Curing Conditions on Chloride Resistance of BCCP
The chloride diffusion coefficients, compressive strength, and water absorption rates of fine aggregate concrete cover blocks of Bar-wrapped Cylinder Concrete Pressure Pipes (BCCPs) were examined under standard curing (s), low pressure curing (0.7p), steam curing (ZS), and steam-low pressure curing (Z0.7p) to study the influence of curing methods on BCCP’s resistance to chloride. The influence degree of each factor was compared using grey correlation analysis. Results show that the resistance to chloride ingress of concrete increased with the increase of curing age and the chloride resistance of concrete with single mineral powder demonstrated the best performance. The utilization of high sulfate-resistant cement will reduce the chlorine resistance of concrete. At early stages, the resistance to chloride ingress of concrete cured under low pressure (0.7P) and steam (ZS) was higher than that cured under standard conditions (S), while over time, this trend reversed. Furthermore, 0.7P will not damage the interior of steam cured concrete (Z0.7P), but will improve the compactness of concrete. Therefore, the chloride diffusion coefficient of concrete is S >0.7P>ZS>Z0.7P prior to 14 days of curing age, while it will change to ZS>Z0.7P>0.7P>S after 28 days. In addition, curing air pressure and humidity have the greatest influence on the chloride ion permeability of concrete, followed by curing temperature, and curing age has the least influence.
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