Bertha completed its journey under Seattle in April, but the massive boring machine is still in the ground — sort of.
Since the machine is among the largest of its kind, Bertha has to be taken apart piece-by-piece. A recently released video by the Washington State Department of Transportation shows the deconstruction process since April.
That’s what crews have been doing 24/7 since reaching the surface. They have to use torches to break the steel parts down into smaller pieces. Seattle company Nucor is recycling much of that steel.
As Bertha’s outer shell is peeled away, the machine’s mechanical muscles and inner skeleton are being revealed. The cutterhead — weighing 900 tons– was first removed first. Crews cut this portion of Bertha into smaller pieces to be lifted out using a crane. The cutterhead was composed of eight spokes. It took at least 35 crane lifts to remove the entire section.
The back end of Bertha is also being deconstructed inside the tunnel. Those pieces are traveling under Seattle and are being removed out the south end of the tunnel.
Construction crews are also working on the roadways inside the tunnel. So far, 66 percent of the southbound road — upper deck — has been completed along with the walls around it.
The $3.1 billion tunnel project is scheduled to open in 2019, about 4 years behind schedule.