Capillary absorption and concrete durability
ABSTRACT: Concrete quality, and especially reinforcement coating quality, is associated with structure durability. The vulnerability of this coating to aggressive ions and water is evaluated by means of capillary absorption tests. This study presents results from experimental investigations using Ordinary Concrete Mixtures (OPC) and High Resistance Concrete (HSC). We obtained the sorptivity index (s) and the absorption parameters of the Fagerlund Method: water penetration resistance (m), capillary absorption coefficient (k) and effective porosity (εe). Relationship between sorptivity and the Fagerlund parameters was analyzed, and this resulted in a high significance for concrete with effective porosity between 7 and 12%. In addition, a correlation coefficient of 0.982 between m and s was obtained. Sorptivity values are within the acceptable range for water penetration used as criterion of durability by Ho and Lewis. An additional advantage of using sorptivity is its relationship with the Theory of unsaturated flow, by means of which the diffusivity of water can be determined.