Performance as the Criteria for the Durability in Concrete Mix Proportioning

Usually, a concrete mix is proportioned to satisfy the three criteria: strength, workability, and durability. The durability is met by prescribing certain minimum cement content, minimum compressive strength, maximum water-binder ratio, and more parameters suited to concrete exposure conditions. The abovementioned criteria often reflect unsatisfactory results and underestimate the potential of the supplementary cementitious materials. It is a general opinion that concrete’s resistance against the penetration of aggressive media reflects the accurate picture of durability. Given the above, some experimental studies have been conducted expressing the durability of coulombs (charge passed from one end to the other) due to chloride ion penetration. This charge is linked to different water-binder ratios and percentages of supplementary cementitious materials (SCMs) to varying days of curing. This data will be helpful to the mix designer for proportioning the concrete by expressing the durability in terms of chloride ion permeability.