Seattle Tunnel Partners released a new schedule this week for the repair of the damaged seals on the Bertha Tunnel Boring Machine. This revised schedule shows that the TBM won’t be digging again until March […]
Seattle Tunnel Partners has released a conceptual plan showing what the excavation of the pit will look like to repair the damaged Bertha Tunnel Boring Machine. See below. A pit 120 feet deep and 83 […]
Seattle Tunnel Partners and WSDOT are moving forward with the plans to excavate a 120 foot deep shaft to repair the Bertha Tunnel Boring Machine. Unfortunately, there are archaeological issues since the project team did […]
WSDOT announced on Valentine’s Day that the plan to repair the damaged Bertha TBM was not ready yet, as engineers from Hitachi Zosen, the machine’s manufacturer, would need until the end of the month to […]
WSDOT released an update on February 7 with some conclusions regarding the blockage that has stopped the Alaska Way Viaduct Tunnel Boring Machine, Bertha’s progress since December 6. Now they don’t think it was necessarily the well casing after all.
They cite two factors that contributed to the blockage. First, the cutterhead was clogged with material. You can see an cool short video of a worker unclogging the cutterhead. Not terribly dramatic, but still cool. The second factor was increased temperatures inside the equipment. STP discovered damage to a seal that protects the machine’s main bearing. They are still determining how the repairs will be done.
If you want to follow the chronology of this issue, read below for summaries and links to previous updates from WSDOT. And Check out the videos too! [Source: WSDOT]
The Seattle Tunnel Partners JV is attempting to remove the rest of an 8 inch diameter steel well casing that has been blocking the Bertha tunnel boring machine since December 8, 2013. The upper 55 […]
WSDOT held a press conference on Friday to discuss findings regarding the obstruction that had stalled the Bertha Tunnel Boring Machine since December 6. It is an 8 inch well casing, 119 feet deep from […]
Perhaps you’ve heard of Bertha, the World’s Largest Tunnel Boring Machine or TBM? She’s currently working her way underneath Downtown Seattle, excavating the Alaska Way Bored Tunnel to replace the aging Alaska Way Viaduct. This $2 Billion megaproject is an incredible feat of engineering on so many levels. I was in Seattle in September for the Association of Engineering Geologists annual meeting, and was fortunate enough to attend a field trip to see the launch pit and Bertha before she began her tunnel drive. It was an unforgettable experience for this engineer! In this article I give an overview of the project and Bertha herself, discuss some of the geotechnical features, and share my photos and video. Check it out!
The world’s largest Tunnel Boring Machine or TBM just arrived in Seattle last week from Japan. Hitachi Zosen Corp built the 57 foot diameter TBM and tested it before disassembling it for the journey by […]