Effect Of Quartz Particle Size and Cement Replacement on Portland Limestone Cement properties

Abstract

This research focuses on investigating the effect of quartz particle sizeand cement replacement on their physicomechnical properties. Portlandlimestone cement (PLC) was employed and replaced with quartz powder(QP) at various particle sizes (1.19 mm, 425 µm, 300 µm, 212 µm, <212µm) and cement replacement between 2.5 wt.% ~ 15 wt.% at interval of2.5 wt.% to study their impact on the cement properties. The PLC chemical composition revealed a relatively low lime and high silica contentcompared to the conventional cement. QP revealed a high silica, lime andsulphur contents compared to natural sand. A high consistence, elongatedsetting times and lower strengths and specific gravities were observed ascement was replaced with QP at a given particle size respectively. Theeffect of replacing cement with QP content between 2.5 wt.% and 15 wt.%at various particle sizes resulted in average increments by 45.32%, 23.13%and 36.06% for initial setting time, final setting time and water demandrespectively. This increase could be related with clinker diminution coupled with enhanced QP surface area and clinker diminution. Similarly, anincrease in the QP surface area at a given cement replacement led to higherwater consistence, retarded setting times and lower strength. The effect ofenhancing the QP’ surface area between 1.19 mm and below 212 µm at agiven cement replacement resulted in average increments by 26.27%, 8.61%and 7.49% for initial and final setting times and water demand respectively.The strength gain of the QP cement blend diminished significantly above30% up to 15 wt.% cement replacement especially beyond 3 days. The lowstrength could be due to the high-water consistence linked with silica content resulting in setting time retardation. The optimal QP content was determined at 5 wt.% owing to the fact that the physicomechnical properties didnot significantly deviate from the properties of control.