Produce fly ash aggregate and application of fly ash aggregate in mortar

Abstract

The aim of the research are to create aggregates from fly ash and use fly ash aggregates to partially replace natural aggregates in mortar. In this study, fly ash was combined with cement, and liquid glass. Fly ash aggregates were dried at 100°C for 24 hours to create hardness. Fly ash aggregates were used to replace sand in proportions of 0%, 10%, 30%, and 50% by volume in cement mortar. The flow and compressive strength of the mortar under two different curing conditions were investigated. The first, the samples were immersed in water full time. Second, the samples were cured for 7 days in water and then kept in air. The results were shown that the flow of the mortar was decreased as the sand replacement ratio with fly ash aggregate increased. Under combined curing conditions of 7 days in water and then kept in air, the compressive strength of mortar using 10% fly ash aggregate was higher than that of the control sample. The strength of mortar using fly ash aggregates at 28 days and 91 days of age was improved when mortar was cured under non-standard conditions (in air) when compared to samples completely immersed in water.

Keywords: Fly ash aggregate; flow; compressive strength; mortar; curing.