Workability and compressive strength properties of normal weight concrete using high dosage of fly ash as cement replacement

This study evaluates the workability and compressive strength properties of normal weight concrete (NWC) using high dosage of fly ash cement replacement. The goal is to find the suitable mix proportion of G40 NWC and to study the slump-loss at different interval time with fly ash replacement up to 60%. The strength properties of NWC were investigated using rebound hammer test as non-destructive and compressive strength test for verifying it. The acceptable mix proportion for fly ash replacement was then investigated using laboratory experiments. For strength properties of NWC, the samples were tested for 3, 7, 14 and 28 days. Results indicate that the inclusion of fly ash as partial cement replacement improves the workability of NWC concrete. The slump-loss of NWC with fly ash increases and it delays the setting time of fresh concrete. The strength of concrete reduces with an increment of fly ash. The strength measured using non-destructive test is lower when compared to compressive strength test. The results demonstrate that the replacement of cement with fly ash in concrete is beneficial and the targeted strength of concrete will achieve with time.