This book introduces the research background and significance of carbon emissions in the tunnel industry and systematically reviewed the research progresses of carbon emission researches for tunnels, LCA (life cycle assessment) research framework, and uncertainty research progress. The authors propose a novel modular carbon emission calculation method for highway tunnel construction and expounds on the modular LCA system boundary theory of tunnel construction. This method does not require abundant knowledge of LCA modeling, which is convenient for general engineering and technical...