Study on Large Deformation Prediction and Control Technology of Carbonaceous Slate Tunnel in Lixiang Railway
Table 5
Comparison of design and optimization of original tunnel construction support parameters.
Surrounding rock grade
Geological conditions
Primary support
Reserved deformation
Secondary lining
Original V
Generally buried deep and moderately weathered
C25 shotcrete 26 cm, I20b steel frame spacing 50 cm/frame, 3.0 m long φ 22 hollow anchor rod with longitudinal circumferential spacing of 80 and 100 cm
600 mm
40 cm thick C30-reinforced concrete
Original Vstrengthen
Deep buried strong weathering
Spray C30 concrete for 30 cm and hang HPB 300 φ 8 reinforcement mesh, I22b steel frame, spacing 50 cm/frame, 3.5 m long φ 25 hollow anchor rod with longitudinal circumferential spacing of 50 and 80 cm
800 mm
50 cm thick C30-reinforced concrete
Optimized V
Generally buried deep and moderately weathered
Spray C30 concrete for 30 cm and hang HPB 300 φ 8 reinforcement mesh, I22b steel frame, spacing 50 cm/frame, 3.5 m long φ 25 hollow anchor rod with longitudinal circumferential spacing of 50 and 80 cm
700 mm
50 cm thick C30-reinforced concrete
Optimized Vstrengthen
Deep buried strong weathering
Spray C40 concrete 32 cm, hang HPB300 φ 8 reinforcement mesh, I25b steel frame, spacing 50 cm/frame, 4.0 m long φ 26 hollow anchor rod with longitudinal circumferential spacing of 40 and 80 cm
