A holistic model for cement paste and concrete chloride diffusion coefficient

Strength and durability are pivotal for designing sustainable concrete structures. For reinforced concrete, chloride diffusion coefficient is a measure for durability. Phenomenological multi-scale models are proposed for quantifying chloride effective diffusion coefficient of bulk cement paste (DClbcp) and concrete (DClc). DClbcp model accounts for w/cm, and cement composition and degree of hydration. DClc model comprises of DClbcp, tortuosity factor and ITZ, interfacial transition zone, factor sub-models. DClbcp and DClc models results are statistically equal with 95% confidence to the experimental values and possess high accuracy and precision for a wide range of w/cm, cement content and composition, aggregate content and age. DClbcp and DClc models' results have an overall error of 12% and 11%, respectively. The errors in DClc model results are less than the standard test method repeatability and the coefficient of variation of the reproducibility. DClc model standard error, COV and R2 values are 0.36 × 10−12 m2/s, 26% and 0.94.