Fly ash as supplementary cementitous material reinforced concrete block / Nur Athirah Mohd Adzali and Nurhasyimah Ahmad Zamri

The largest environmental issue with cement and concrete production is energy usage. According to the National Ready Mixed Concrete Association, 0.9 pounds of carbon dioxide are released for every pound of concrete. Due to the growing use of concrete, the industry’s carbon dioxide emissions are constantly rising. All coal combustion power plants produce unused fly ash and bottom ash, which lead to environmental problems such as air pollution and groundwater contamination. This is primarily due to the leaching of metals from the ashes, with a significant concern being the accumulation of fine particles in fly ash. Cement replacements such as Pulverised Fuel Ash (PFA) and Ground Granulated Blast-furnace Slag (GGBS) can save 850 kg of carbon dioxide for every tonne of Portland cement replaced. Fly ash is also recognised as an environmentally friendly material because it is a byproduct and has low embodied energy.