Greenhouse gas emissions associated with traditional and alternative concretes

Abstract

Life Cycle Assessment (LCA) quantifies the environmental impacts associated with products throughout their life cycle. LCA also assists in the interpretation of impact assessment results, enabling improvements in a product or process. This paper applied the LCA methodology to quantify and compare the greenhouse gas emissions associated with different types of concrete: with a traditional binder (Portland cement) and with alkali-activated materials (Metakaolin, Lateritic Soil, and Lateritic Concretion) as precursors. The environmental impact was evaluated using greenhouse gas emissions (kg CO2-eq/m³), considering 1 m³ of each binder and resistance of approximately 30 MPa, obtained by a recommended mix ratio. The main objective is to evaluate whether alkali-activated binders present lower emissions than Portland cement. The results demonstrated that Portland cement is responsible for over 92% of the emissions associated with traditional concrete production. The use of alternative materials in civil construction, such as laterite soil, reduces carbon dioxide emissions by 79% compared to traditional concrete.

Keywords

• alkali-activated materials
• concrete
• life cycle assessment
• portland cement