Research on the production of fly ash based-lightweight aggregate for concrete

Abstract

This work investigates the feasibility of production of lightweight aggregate (LWA) using local fly ash in the Mekong Delta region by the cold bonding method. LWA was produced by adding 3-14% cement to fly ash by pelletization process. The tap water was used as a wetting agent. The selected LWAs were used as coarse aggregate for producing lightweight concrete (LWC). Results showed that LWA with bulk density of around l.Q g/cm3, water absorption in the range of 12.8-16%, and crushing strength as high as 1.14 MPa can be produced, Tire 28-day compressive sLrength values of LWCs were in the range of 17.5-25.1 MPa at the water-to-cement ratio of 0.30. There was a significant reduction in the dry unit weight of LWC, reaching 1.87 g/cm3. The water absorption of LWC was higher than that of normal concrete.