3.4K views · 40 reactions | Water ingress poses a significant risk in...

TBM breakthrough into a secant piling reception shaft. In tunnelling projects where a Tunnel Boring Machine (TBM) breakthrough occurs into a reception shaft supported by secant piling or Diaphragm walling, the inclusion of a soft eye within the structure facilitates a smoother breakthrough for the TBM. Secant piling provides structural support to the shaft by creating a continuous wall of interlocking piles, which helps to stabilise the surrounding soil or rock. The soft eye acts as a predetermi