SEATTLE — Bertha, the world’s largest tunnel boring machine, is in position to be torn apart so it can be repaired.
State transportation officials say the broken machine reached a stopping point inside the rescue pit late Tuesday, clearing the way for workers to start the disassembly process.
The tunnel is being built to replace the Alaskan Way Viaduct, damaged in a 2001 earthquake. The machine started digging in the summer of 2013, but broke down in December. 2013.
Bertha moved forward 57 feet since Feb. 17 in its effort to reach the pit. Along the way, the machine built nine concrete tunnel rings.
Now that Bertha is in place, workers will disconnect hoses and cables, remove motors and prepare to lift four pieces weighing 2,000 tons to the surface for repairs.
