Toward salt-scaling resistant concrete
The main objective of this research study was to (1) improve the understanding of the underlying mechanisms of durability-related deterioration in pavements; (2) improve the understanding of methods for extending pavement life, i.e., mixture ingredients; and (3) implement tools and specifications that will increase the longevity of concrete pavements. To this end, since it was of special interest to enhance current knowledge regarding salt-scaling resistance of concrete, an extensive effort was made in conducting a comprehensive literature review on the topic, after which an experimental program was designed to study the (i) relationship between the air-void system and salt scaling, (ii) effect of mixture components on hardened concrete properties and salt-scaling potential, (iii) impact of workmanship, i.e., effects of different finishing times and curing regimes on the scaling resistance of the concrete specimens, and (iv) correlation between concretes’ hardened properties and salt-scaling resistance. Statistical univariate and multivariable regression models were developed for use by researchers and field engineers, using non-destructive tests, i.e., ultrasonic pulse velocity (UPV) and rebound hammer (RH), to facilitate the prediction of concretes’ hardened properties and salt-scaling resistance. Ultimately, the contributions of each of the investigated factors on concretes’ hardened properties and salt scaling resistance were statistically investigated and corresponding multivariate-regression models were developed.
The collection of mixture variables included water-to-cementitious materials (w/cm) ratio, paste volume, slag cement, and air content. Concrete performance was mainly investigated through tests of abrasion resistance, sorptivity, compressive strength, and salt scaling. Shrinkage and freeze-thaw resistance of the concrete mixtures were also tested to evaluate the effects of paste volume on concrete’s hardened properties. Finally, research continues toward assessing the correlation between cement chemistry and salt-scaling damage.