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 (DCl bcp) and concrete (DCl c). DCl bcp model accounts for w/cm, and cement composition and degree of hydration. DCl c model comprises of DCl bcp, tortuosity factor and ITZ, interfacial transition zone, factor sub-models. DCl bcp and DCl c 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. DCl bcp and DCl c models' results have an overall error of 12% and 11%, respectively. The errors in DCl c model results are less than the standard test method repeatability and the coefficient of variation of the reproducibility. DCl c model standard error, COV and R2 values are 0.36 × 10−12 m2/s, 26% and 0.94.