Influence of cement strength class on environmental impact of concrete

摘要

Traditional approaches to reducing the CO2 emissions of cement production are effective yet insufficient, which has driven new research and innovations. A potential alternative that has been poorly explored is optimizing the physical and chemical characteristics of cement to enhance the dosage efficiency for concrete, which can reduce both cement consumption and CO2 emissions. This approach demands an understanding of the potential savings according to the cement strength. In practical terms, increasing the cement strength requires more electric energy to grind cement into finer particles, which ensures that most of the clinker and other reactive particles are hydrated at 28 days; and increasing the reactive phases of the cement, such as the clinker content. Both options improve cement reactivity and can reduce cement consumption to achieve the same mechanical performance of concrete. The objective of this study was to investigate the potential reduction in the CO2 footprint of concrete mixes with cements of different strength classes and discrete clinker substitution ratios. The effect of grinding finer cement on reactivity was also evaluated. The carbon abatement costs were estimated according to the additional CO2 emissions from cement grinding and potential CO2 reduction from a smaller dosage.