| The ingress of chloride ions from road salts and soil poses one of the most potent threats to reinforced concrete structures. This threat is exacerbated by damage due to freeze-thaw cycling. While the details of this phenomena are well documented, the effects of constant low temperatures on concrete are unknown.; This thesis describes the procedure followed, and results obtained from, an experimental research program. The research evaluates several transport properties during and after the subjection of concrete to depressed temperatures or freeze thaw cycling treatments. The results of the experiments show clear trends in the coefficient of permeability and the diffusivity when treated to the various treatments. It was concluded that there is a coupling effect between the permeability coefficient, freeze-thaw damage, and depressed temperature treatments. The permeability increased with increased exposure to cycling or depressed temperatures, indicating that these treatments damage the pore structure of the concrete. In addition, it was found that there is a relationship between freezing time, freeze-thaw damage, and chloride ingress. The freezing of the pore water slows the ingress of chloride ions while damage to the pore structure increases the rate at which ions can penetrate. |
