SOME RECOMMENDATIONS ON THE USE OF DUSTY CRUSHED STONE AS FINE AGGREGATE FOR CONCRETE MIX PROPORTION

Abstract

Dusty crushed stone is a byproduct in the sieving process of stone manufacture at the quarries. This kind of crushed stone can be used as a fine aggregate instead of river sand in the conventional concrete mix design. The authors have carried out a preliminary research and are able to give some recommendations on the use of dusty crushed stone for concrete. First, when using this stone it is necessary to study its mechanical properties as well as particle size distribution. Next, in the concrete mix design the cement content should not be exceed 10% in comparison with the conventional mix using river sand as fine aggregate. And finally, the chemical admixture should be added into concrete mixture in order to increase the workability of fresh concrete, as well as to enhance concrete strength at early age (3 and 7 days) significantly.