Title: Influence of Chloride Solution Concentration on Deicer Salt Scaling Deterioration of Concrete

Author(s): J. Marchand, M. Pigeon, D. Bager, and C. Talbot

Publication: Materials Journal

Volume: 96

Issue: 4

Appears on pages(s): 429-435

Keywords: deicers; ice formation; porosity

DOI: 10.14359/642

Date: 7/1/1999

Abstract:
To analyze the influence of the chloride solution concentration on the deicer salt scaling deterioration of concrete, three concrete mixes [with water-cement ratios (w/c) of 0.25, 0.35, and 0.45] were prepared and cured in a saturated lime solution for 180 days. At the end of the curing period, all concrete specimens were dried at 20 C and 50 percent relative humidity (RH) for three weeks. For each concrete mix, a first series of specimens was resaturated with chloride solutions at various concentrations (in the 0 to 12 percent range). Another series of specimens was resaturated with pure water. After a three-week resaturation period, all concrete specimens were tested in accordance with ASTM C 672. The specimens resaturated with a chloride solution were tested with the same solution on the surface. The specimens resaturated with water were tested with chloride solutions at different concentrations (always in the 0 to 12 percent range). In addition, the pore structure characteristics of each concrete mix was investigated by mercury intrusion porosimetry, and low temperature calorimetry was used to measure ice formation after the drying-resaturation treatment. The test results indicate that low chloride concentrations (in the 2 to 4 percent range) always produce more scaling, irrespective of the w/c. No significant difference was found between the specimens resaturated with a chloride solution and those resaturated with water. According to these results, it is the concentration of the outer solution that has the highest influence on the scaling mechanisms.