News
Building the Tunnel Behind Bertha
This is a great little time lapse video from WSDOT that shows the construction of the tunnel behind the Bertha’s disassembly pit for the Alaska Way Viaduct Replacement Project.
bertha
Miscellaneous
Happy National Tunneling Day (UK)
The British Tunnelling Society (BTS) is encouraging our profession and the public to celebrate National Tunneling Day today, December 7. Their goal is to promote the industry (and its many professions) to students of all ages […]
Project Related
Breakthrough! Bertha TBM Completes Alaskan Way Viaduct Tunnel in Seattle
After tunneling 9,270 feet under downtown Seattle, the Bertha tunnel boring machine finally broke through at the north portal yesterday. The breakthrough marks a major milestone in the project to replace the seismically deficient SR-99 […]
Project Related
Underneath Seattle: Working Under Pressure to Keep Bertha Moving
Every tunneling machine needs its cutting tools replaced every now and then. But the challenge is keeping a giant machine sharp while a wall of waterlogged earth looms in front. Welcome to the world of […]
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The Building Blocks of the SR 99 Tunnel
The tunnel liner that is being placed by the Bertha tunnel boring machine consists of precast concrete segments. This video by the WSDOT shows how they are made at the casting yard, and what Bertha […]
Available Resources
Video: Changing cutting tools on Bertha TBM
This is an interesting video of crews changing cutterhead teeth on the Bertha TBM beneath downtown Seattle. [Source: WSDOT YouTube Channel. Image: YouTube]
Available Resources
Video: Inside tunneling under the Alaskan Way Viaduct
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 […]
Available Resources
Video: Monitoring the ground and buildings during SR 99 tunnel construction
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 […]
Project Related
Bertha Demo Period Done, Resumes Mining
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 […]
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More Trouble for Bertha TBM, Sinkhole, Tunneling Suspended
The Bertha TBM creating the Alaska Way Viaduct Replacement Tunnel and the Seattle Tunnel Partners JV just can’t seem to catch a break. After being stopped for nearly 2 years to replace the entire cutterhead […]