Geotechnical consultant Gregg Korbin served on the Technical Advisory Board for Washington State DOT for the SR-99 Alaskan Way Viaduct Replacement Tunnel Project. He recently presented to the Vancouver Geotechnical Society on lessons learned from […]
A debris-laden landslide has closed SR 706, the popular road from Ashford, Washington to Mt. Ranier National Park. The road was first closed on February 6 as portions of the highway were covered with debris […]
From WSDOT’s video description: After nearly a week of tunneling under the Alaskan Way Viaduct, crews are steadily continuing Bertha’s underground drive towards downtown Seattle. This video gives you a behind-the-scenes glimpse into how the […]
This is a great video from WSDOT visualizing all of the geotechnical instrumentation and survey monitoring being done in Downtown Seattle above the Bertha TBM for the Alaska Way Viaduct Replacement project. Soldata is the […]
The Bertha tunnel boring machine has resumed chewing away beneath Seattle after a ‘suspension for cause’ order from WSDOT shut it down in January following two safety incidents. The BTM began tunneling with some conditions […]
The Seattle Tunnel Partners JV announced last month that tunneling on the Alaska Way Viaduct Replacement project will resume a month later than originally planned. The Bertha TBM will resume mining on December 23 after […]
The Alaskan Way Viaduct tunneling project was in the news late last year when settlement of the Viaduct was reported during the dewatering efforts for the Bertha TBM rescue shaft. A recent post by WSDOT […]
There hasn’t been much to report recently for the Alaskan Way Viaduct Tunnel Project in Seattle. As you probably know, Bertha has not advanced since about December of 2013 after drilling through an abandoned steel […]
The WSDOT announced recently that the Seattle Tunnel Partners Joint Venture has requested a total of $188 million in change orders so far, and that the Department has denied $157 million of those, with $31 […]
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]