Achieving Sustainability by the Utilization of Fly Ash as a Secondary Cementitious Material

Abstract

It is well recognized fact that to reduce the greenhouse effect due to emission of CO2 during the production of cement, fly ash is being added as one of the supplementary cementitious materials. Sustainability of the concrete made up of fly ash incorporated cement is very important. The meaning for sustainability of concrete in the present context is (i) to reduce the pollution levels by the addition of fly ash in concrete (ii) the performance of concrete (mechanical and durability properties) should be comparable with the conventional concrete. Keeping in view of this, in the present study, life cycle analysis was carried out for the concrete mixes of 400 kg/m³ with the water binder ratio being 0.4 and varying percentages of fly ash from 0, 10, 20, 30, 40, 50 and 60. Part of the study, compressive strength, durability properties like RCP test and acid attack tests for the curing ages of 28, 56 and 90 days were evaluated.  From the experiments, it was majorly observed that (i) percentage of fly ash up to 40% replacement yields the sustainability aspect by continuous pozzolanic action (ii) 50% reduction in CO₂ emission and economy is realized by the optimum utilization of fly ash