Experiment and Modeling of the Effect of Aggregate Shape on the Chloride Diffusivity of Concrete

Abstract

The purpose of this paper is to evaluate the effect of aggregate shape on the chloride diffusivity of concrete through laboratory experiments and theoretical analysis. In the experiment, three types of crystal glass spheroids with aspect ratios of 1, 2, and 3 are used as coarse aggregate. The experimental results show that the chloride diffusivity of concrete decreases with an increase in aggregate aspect ratio. When the coarse aggregate volume fraction is equal to 0.1, 0.2, and 0.3, the chloride diffusivity of concrete at an aggregate aspect ratio of 3 is, on average, smaller than that at an aggregate aspect ratio of 1 by 5.29%, 11.4%, and 19.6%, respectively. An analytical approximate is derived for the chloride diffusivity of concrete with spheroidal aggregates and verified with the experimental results. The analytical approximate can predict the chloride diffusivity with an average relative error of less than 8%.