Towards a sustainable concrete: "Sandless" concrete

Abstract

As a step towards ensuring the sustainability of concrete as a construction material, an investigation was carried out on the mechanical and durability properties of concrete made without natural sand, termed "sandless" concrete, and with cement partially replaced by fly ash. Four groups of concrete mixes, with water-cement (w/c) ratios of 0.40, 0.45, 0.50 and 0.55, respectively, were studied. For each w/c ratio, there were six mixes with 0, 10%, 20%, 30%, 40% and 50% of cement content replaced by fly ash by mass, and one normal concrete mix containing natural sand. The difference in mechanical properties between normal and "sandless" concrete was not significant. "Sandless" concrete mixes with cement replaced by fly ash by