굴착손상영역(EDZ)이 지하수 유입에 미치는 영향과 그라우팅 최적화 연구

초록

This study aims to quantitatively investigate the impact of the excavation damaged zone (EDZ), formed during tunnel excavation, on groundwater inflow, and to propose an optimized grouting design strategy for effective mitigation. Targeting rock mass classes IV and V, this study analyzes the influence of EDZ characteristics, hydraulic property changes, and variations in grouting permeability and thickness by applying analytical equations and PLAXIS 2D-based numerical simulations. The results show that the presence of the EDZ significantly increases groundwater inflow paths, becoming a major factor in tunnel instability. Reducing the permeability of the grouting material and ensuring sufficient grouting thickness were found to be critical in lowering inflow rates. In particular, when the grouting permeability ratio was 1/100 and the thickness exceeded 1.5–2.0 m, more than 95% sealing efficiency was achieved, and the analytical and numerical results showed close agreement. Therefore, this study offers a quantitative grouting design methodology that considers both cost-effectiveness and technical reliability for future tunnel engineering applications.

키워드