May 29 project update: New parts for Bertha arrive at Terminal 46
The SR 99 tunneling machine’s new inner seals arrived from Japan as scheduled this week. The pieces, which are integral to Seattle Tunnel Partners’ effort to repair the machine, were offloaded at Terminal 46 and trucked a short distance north to the repair area. The piece shown below is the new inner seal ring, which houses the rubber seals that will protect the new main bearing. Additional photos of crews transporting the piece are available on Flickr.
- A new main bearing
- Enhanced monitoring systems
- Added steel to strengthen the machine and accommodate the new seal system
- Widened openings at the center of the cutterhead
- Extended arms to mix excavated soil in the chamber behind the cutterhead
- Narrated video explaining STP's repair plan (links to YouTube)
- Seattle Tunnel Partners repair work plan (pdf 4.8 Mb)
- Three-angle time-lapse video of Bertha's front end lift (links to YouTube)
- Single-angle time-lapse video of Bertha's front end lift (links to YouTube)
- Time-lapse video of Bertha's first piece rising to the surface (links to YouTube)
- Time-lapse video of Bertha parking in the pit (links to YouTube)
- Video of Bertha's breakthrough (links to YouTube)
- Video of crews chipping a Bertha-sized circle on the face of the pit’s southern wall (links to YouTube).