Assessing recycled concrete’s sustainability with emergy theory and input-output modeling

Abstract

This study is the first to integrate emergy theory, life cycle assessment (LCA), and input-output analysis (IOA) to analyze the environmental performance of conventional concrete (CC) , recycled coarse aggregate concrete (RAC), recycled fine aggregate concrete (RFC), and recycled powder concrete (RPC). It comprehensively covers the entire life cycle from raw material extraction to waste disposal, employing dynamic emergy flowcharts to visually represent emergy inputs and pollutant emissions at each stage. An emergy-based input-output emission coefficient is introduced to standardize environmental impacts across different material flows, enhancing evaluation accuracy and comparability. The findings reveal that recycled concrete significantly reduces emergy consumption and pollutant emissions, especially in cement production, where its reduction potential is most pronounced. This study contributes an innovative emergy-input-output evaluation framework based on Cradle to Cradle (C2C) principles, facilitating the optimization and selection of sustainable building materials.