유한요소 수치해석을 통한 저탄소 콘크리트라이닝에서의 터널 안정성 예측

Efforts to reduce carbon emissions are essential for a sustainable transition in the construction industry. To respond to this challenge, the potential of low-carbon concrete for tunnel's concrete lining applications was evaluated, focusing on both environmental benefits and structural stability. By replacing ordinary Portland cement (OPC) with ground granulated blast furnace slag (GGBS) and fly ash (FA) in varying proportions, CO2 emissions were reduced by up to 65% per cubic meter compared to conventional concrete. Finite element analysis (FEA) using PLAXIS 3D was conducted to investigate the structural performance of materials under different ground loss and earth pressure coefficients. The analysis revealed that axial force, shear force, and bending moment were significantly influenced by material properties. High-replacement-rate concretes (R70, R90) exhibited lower safety factors for shear forces due to reduced early strength, while achieving higher safety factors for axial forces and bending moments, which can be attributed to enhanced stiffness and load redistribution characteristics. For all scenarios, low-carbon concrete kept safety factors above 1.0, satisfying structural design standards. These results highlight the potential of high-replacement low-carbon concrete to significantly reduce environmental impact while maintaining structural safety, offering a feasible alternative for future construction projects. In addition, this study established a foundation for sustainable construction technologies and carbon-neutral goals by applying low-carbon concrete to the tunnel lining process through numerical analysis.