Towards Sustainable Tunnelling: An Integrated Framework for Carbon Assessments in TBM Tunnels

This paper addresses the urgent need for a comprehensive carbon assessment framework in tunnelling construction to achieve Net Zero Carbon by 2050. Current practices lack granularity and specificity, particularly for Tunnel Boring Machine (TBM) tunnelling, which hinders the identification of early carbon reduction potentials. To overcome these issues, this paper proposes applying the EN 15978 system boundary to tunnelling projects. This innovative framework emphasizes the importance of early design decisions, particularly in the selection of materials and specifications for segmental linings and the performance modelling of TBMs. The proposed method, validated through case studies, paves the way for better estimation and reduction of greenhouse gas emissions in TBM tunnelling. This holistic approach contributes to the broader goal of decarbonization in the construction sector, supporting global efforts towards sustainable development.