162 equipment components influence the embodied carbon footprint of underground development systems. Life-cycle assessments in heavy machinery industries demonstrate that component remanufacturing can significantly reduce embodied emissions compared to new production. Mechanized tunnelling equipment can be designed for modular refurbishment and redeployment across multiple project cycles. Remanufacturing approaches reduce material demand and associated emissions compared to single-use equipment configurations, supporting circular economy principles in capital-intensive industries. At the same time, regulatory frameworks such as the European Corporate Sustainability Reporting Directive (CSRD) require companies to assess environmental impacts across their value chains. Double materiality analyses evaluate both financial risk exposure and environmental impact contribution. In this regulatory environment, excavation systems are increasingly assessed not only on productivity but also on energy efficiency, emission intensity, and lifecycle resource performance. 5.5 Sustainability as a System-Level Attribute The sustainability performance of underground development is determined by the interaction of excavation geometry, energy demand stability, infrastructure integration, lifecycle management, and risk distribution. Continuous mechanized excavation represents a system configuration that structurally aligns with electrification strategies, integrated infrastructure planning, and stable energy profiles. Drill-and-blast retains advantages in flexibility and lower initial capital intensity but embeds higher short-cycle variability and diesel dependency. The selection between cyclic and continuous excavation should therefore be understood as a strategic choice between development architectures, particularly in projects where long drive lengths, electrification pathways, and sustainability targets converge. 6. CONCLUSION AND OUTLOOK The comparison between cyclic drill-and-blast and continuous mechanized excavation extends beyond differences in equipment or advance rate. It reflects a fundamental distinction in process architecture, risk distribution, and system integration. Continuous TBM-based development consolidates fragmentation, muck handling, and primary support within a coordinated and largely parallel system. This structural configuration reduces short-cycle variability and shifts operational risk toward engineering definition and machine availability. For long access drives and infrastructure-intensive projects, such redistribution may enhance schedule predictability and influence time-to-ore performance.
RkJQdWJsaXNoZXIy MTM0Mzk2