Adding limestone fines as cement paste replacement to reduce water permeability and sorptivity of concrete

• Adding limestone fines as cement paste replacement can reduce cement content.
• Such use of limestone fines would reduce carbon footprint and risk of cracking.
• It would also reduce permeable porosity and water resistance.

The addition of limestone fines to fill into the voids between aggregate particles can reduce the volume of voids to be filled with cement paste and thus reduce the cement paste volume needed to produce concrete. Apart from decreasing the cement clinker consumption and carbon footprint, this may have other benefits too. In previous studies, the authors have found that the addition of limestone fines as cement paste replacement would substantially improve the dimensional stability. In this study, the authors aimed to evaluate the effects on the water resistance of concrete. For the evaluation, a series of concrete mixes with various water/cement ratios and different limestone fines contents were tested for their workability, strength, water permeability, sorptivity and porosity. It was found that within the ranges of concrete mixes studied, the addition of limestone fines as cement paste replacement would significantly increase the strength and substantially improve the water resistance of the concrete produced.