9:25 p.m. update: After a successful day of lifting, Seattle Tunnel Partners has chosen to wait until morning to place the SR 99 tunneling machine's front end on the repair platform. The piece will remain suspended above the platform until a fresh crew arrives in the morning to complete the lift.
Crews will wait until Tuesday morning to place Bertha on the repair platform.
6:30 p.m. update: Seattle Tunnel Partners is making good progress as they continue to lift the SR 99 tunneling machine’s front end to the surface for repairs. Crews began the lifting process early Monday morning with a series of tests to ensure the massive red crane performing the lift could handle the weight of the 2,000-ton section. The lift began around noon and the piece was visible at the surface a few hours later.
To expedite the lifting process, crews chose to rotate the section into a horizontal position as they hoisted it from the pit. When the rotation is complete, the crane will roll southward on its rails toward the specially made platform where the piece will be set down. The lift won’t likely be completed for several more hours, but there is no set schedule. Crews will take as long as necessary to safely lower the piece to the platform.
Bertha at the start of the lift. Bertha emerges from the pit.
12:30 p.m. update: Seattle Tunnel Partners has begun lifting the SR 99 tunneling machine’s front end to the surface for repairs. A massive red crane began the lift – which includes the machine’s five-story-tall cutterhead – around noon Monday. Because the piece is so large, the lift could take 16 hours or longer, but there is no set schedule. Crews will take as long as necessary to safely complete the lift.
Seattle Tunnel Partners is getting ready to begin lifting the SR 99 tunneling machine’s 2,000-ton front end to the surface for repairs. The first step in the lifting process is to incrementally add weight to the crane to ensure it can safely complete the lift. Because the piece is so large, the entire lift process could take 16 hours or longer, but there is no set schedule. Crews will take as long as necessary to prepare for and execute the lift.
In addition to the machine’s five-story-tall cutterhead, the section being lifted includes the motors and parts that enable the cutterhead to rotate. It also houses the main bearing and seal system that will be replaced during the repairs.
The crane doing the lifting was built by Mammoet, a firm that has performed other large lifts around the world, including the successful recovery of a Russian nuclear submarine
from the bottom of the Barents Sea. Equipped with nearly seven miles of steel cable, the crane bringing Bertha to the surface is capable of lifting more than 2,400 tons. Check out our time-lapse video
(links to YouTube) showing the crane’s assembly.
This will be the fourth and final lift to bring pieces of the tunneling machine to the surface, a process our narrated video
(links to YouTube) explains in detail. To date, crews have removed three pieces of Bertha’s exterior from the pit, the largest weighing 270 tons. The first lift, which occurred on March 19, can be seen from the perspective of the crane operator in this time-lapse video
(links to YouTube).