Cradle for Tunnel Boring Machine SH20

Key Elements:
• Cradle overall was around 18m long and 10m wide
• Made in 4 sections for transport bolted together on site
• Heavy plate Welded beams to support TBM
• Full penetration but welds of diagonal support to frame
• Rail to spread load of TBM and allow it to jack off.


Challenges:
• Fabricate in 4 sections so that all match up. Trial assembly in shop.
• Heavy plate welded beam FPBW to frame at an acute angle
• Unique rail profile to support TBM
• Structural bolted splice joints
• Structure to take unusual loads of TBM jacking forward into the tunnel.