Influence of fines content on durability of slag cement concrete produced with limestone sand

•Effect of limestone sand fines on durability of slag cement concrete was studied.•Statistical analysis was performed to investigate the significance of fines content.•Contribution of fines on durability was more prominent for concretes with higher w/c.•The findings obtained from the field conform with the output of this research. The effectiveness of limestone sand fines (material finer than 0.063mm) in controlling durability performance of slag cement concrete was investigated in an experimental program. Slag cement concrete specimens incorporating limestone aggregate were produced in two water-cement ratios leading to moderate and high-level durability. Linear regression analysis was applied to evaluate the rates and significance of change in durability performance parameters of concrete at varied levels of fines content ranging between 0 and 15%. Significant relationships between performance parameters (compressive strength, water penetration resistance, chloride migration coefficient, resistivity and abrasion resistance) and fines content were found in statistical analysis depending on the water-cement ratio. Compared to low water-cement ratio concrete specimens, the contribution of the fines on durability was more prominent for the concrete mixes with high water-cement ratio. The paper also presents a case-study on durability assessment in an on-going marine infrastructure project involving Izmit Bay Crossing Suspension Bridge. The findings obtained from the field conform with the output of this research.