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Last Update: 10/31/2024 01:04 AM

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Front
Explain how the timing of support installation affects tunnel stability, especially in weak ground conditions. (5 marks)
Back
  • Immediate Ground Control
    • Installing supports (e.g., shotcrete, rock bolts) immediately after excavation helps control ground movement and relieves stress concentration around the tunnel face. Delays can allow loose soil or fractured rock to shift, increasing the risk of collapse and making stabilization more challenging​​.
  • Minimizing Deformation
    • Timely support installation reduces deformation in soft or highly deformable ground, where delayed support can lead to ground settling or excessive tunnel wall convergence. Quick application of initial supports helps maintain the tunnel’s structural shape and stability​​.
  • Load Redistribution
    • Early support installation redistributes ground loads around the tunnel, decreasing the pressure on the face and walls. This is especially important in weak soils, where load redistribution mitigates the risk of progressive failure along the tunnel perimeter​.
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    893839d9-300a-4343-b1a3-abfb175be348

    Current Tags:

    Sequence_of_Support

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