Chloride ingress in portland cement concrete under frost action
Paper in proceedings, 2007
This paper presents the results from the laboratory investigation of chloride ingress in Portland cement concrete under frost action. As a part of doctoral work, six types of Portland cement concrete with w/c from 0.30 to 0.75, five of them with and one without air entraining agent (AEA), were used in the investigation, including the measurements of capillary suction of water and sodium chloride solution with and without frost action, chloride penetration profiles with and without frost action, and scaling and relative ultrasonic pulse transmission time (UPTT) after different freeze-thaw cycles. The results show that none of the six types of concrete revealed any significant sign of external or internal damages after 112 cycles of freeze-thaw, while significant liquid uptakes due to the frost action were found in almost all types of concrete. Consequently, these liquid uptakes accelerated chloride penetration into concrete to some extent.