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Hard grind: The epic journey of the world's biggest tunnel

May 01, 2017 On April 4, the world's largest tunnel boring machine broke through to the open air after almost four years underground. Called Bertha, the giant

Big Bertha -- world's largest tunnel boring machine

Dec 26, 2013 Named after one of Seattle's early mayors, the $80 million drill Big Bertha is 326 feet long, weighs 6,700 tons, and does much more than drill. John Blacksto...

Bertha, Seattle's SR 99 Tunneling Machine, Is Finally Done

Apr 05, 2017 Bertha the tunneling machine broke through a new concrete wall into a disassembly pit. Eventually engineers determined that seals on the main bearing needed replacing 1,

Big Bertha world’s largest tunnel boring machine

Sep 29, 2015 Big Bertha world’s largest tunnel boring machine facing big Seattle challenge Named after one of Seattle’s early mayors, the $80 million drill Big Bertha is 326 feet long, weighs 6,700

Who Killed Bertha? Why the Seattle Tunnel Disaster Isn't

Bertha’s in heavy rotation (above): A giant red crane slowly rotates the SR 99 tunneling machine’s front end from a horizontal to a vertical position as it is lowered into the access pit on Aug. 24, 2015, two years after the incident occurred. This story follows our feature story, "Spin Zone," which appeared in the October 2017 issue of Seattle Business magazine.

Big Bertha's Two-Mile Subterranean Journey Is Almost Over

Jan 26, 2017 More than 150 feet below the streets of Seattle, Bertha presses on, boring a 57.5-foot diameter tunnel underneath the city. The largest tunnel boring machine (TBM) in the world when it

Seattle's Big Bertha Tunneling Machine Is Finally Back on

Jan 08, 2016 We've covered the saga of the SR99 tunneling machine, better known as Bertha, since it broke down after only drilling though just 52 feet in three days of operation. Now the Seattle tunnel

Mystery of Seattle's Tunnel Borer Blockage Solved

Jan 05, 2014 <p>Turns out the object blocking the world’s largest tunnel boring machine isn’t an old steamship or locomotive or alien spaceship.</p> ‘Bertha has been a wonderful experience for Seattle

What's Blocking Bertha, Seattle's 5-Story Tunneling Machine?

Dec 12, 2013 What's Blocking Bertha, Seattle's 5-Story Tunneling Machine? : The Two-Way The giant cutter is designed to bore through rock and soil without a

Meet Big Bertha, The World’s Largest Tunnel Boring Machine

May 24, 2019 Big Bertha was manufactured and supplied by the Hitachi Zosen Corporation to Seattle Tunnel partners for the SR 99 tunneling project. It measures 57.2 feet (17.5 m) in diameter, which makes it the largest tunnel boring machine in history.

Big Bertha world’s largest tunnel boring machine

Sep 30, 2015 Big Bertha world’s largest tunnel boring machine facing big Seattle challenge Named after one of Seattle’s early mayors, the $80 million drill Big Bertha is 326 feet long, weighs 6,700

Goodbye Bertha: Final piece of the tunneling machine

Aug 23, 2017 Bertha broke through into the disassembly pit on April 4, 2017, and shortly thereafter built the tunnel’s final ring. Though the machine’s tunneling and ring-building work was complete, crews couldn’t complete roadway construction at the north portal until it was removed.

Bertha tunnel boring machine Mining Zimbabwe

Jan 23, 2020 Bertha was a 17.5 m diameter tunnel boring machine built specifically for the Washington State Department of Transportation’s (WSDOT) Alaskan Way Viaduct replacement tunnel project in Seattle. It was made by Hitachi Zosen Sakai Works in Osaka, Japan, and the machine’s assembly was completed in Seattle in June 2013. Tunnel boring began on July 30, 2013, with the machine

Gizmag goes inside the world's largest tunnel boring machine

Jul 23, 2013 On Saturday, a tunnel boring machine (TBM) so large that it looks like something out of Thunderbirds was dedicated in the city of Seattle. “Bertha,” as it’s known, is the world’s largest

Massive tunneling machine stuck under downtown Seattle

May 08, 2014 At 57 feet in diameter, it's touted as the world's biggest tunneling machine. It was even given a name, Bertha. But now, after digging just over 1,000 feet, Bertha is broken down and stuck

The World's Largest Tunnel-Boring Machine

Nov 11, 2013 In July, they unleashed Bertha, the world’s largest-diameter tunnel-boring machine. Built in Japan and reassembled in the U.S., Bertha is digging the 1.7-mile tunnel by advancing at an average

#BerthaCam: Watch the giant boring machine at the end of

Apr 03, 2017 Giant tunnel-drill machine Bertha broke into daylight shortly before 11:30 a.m. Tuesday after years of delays. We covered the scene live.

What's Blocking Bertha, Seattle's 5-Story Tunneling Machine?

Dec 12, 2013 What's Blocking Bertha, Seattle's 5-Story Tunneling Machine? : The Two-Way The giant cutter is designed to bore through rock and soil without

Seattle's 'Bertha' is a not-so-lean tunneling machine

Aug 19, 2013 Bertha was assembled in the 80-foot-deep pit and will displace 850,000 cubic yards of soil for the double-level, two-lane tunnel running between 60 and 200 feet below the ground.

'Bertha' to Start Digging to Replace Seattle's Alaskan Way

May 20, 2013 This summer, "Bertha," a 7,000-ton tunnel boring machine, is set to finally make that tunnel a reality when she starts clawing through dirt 80 feet

Bertha breaks through: Watch the tunnel boring machine’s

Apr 03, 2017 Follow Bertha, the SR 99 tunneling machine [WDOT] Bertha is drilling the last 100 feet of the SR 99 tunnel [CS] Foursquare Alaskan Way Viaduct. SR-99, Seattle, WA 98101 Visit Website.

Tunnel Boring Machine "Bertha" Successfully Completed SR

Tunnel Boring Machine "Bertha" Successfully Completed SR 99 Tunnel Project in Seattle Osaka, Japan, May 19, 2017—Hitachi Zosen Corporation(TYO:7004) has announced that the Tunnel Boring Machine (TBM) known as “Bertha” has successfully completed mining for the SR 99 Alaskan Way Viaduct Replacement Project in Seattle.

Tunnel timeline: From conception to tunnel completion to

Dec 13, 2019 The tunneling machine known as Bertha is completely dissembled and removed from the receiving pit. December 2017 State transportation officials begin discussing what tolls will be implemented once

Meet Big Bertha, The World’s Largest Tunnel Boring Machine

May 24, 2019 Big Bertha was manufactured and supplied by the Hitachi Zosen Corporation to Seattle Tunnel partners for the SR 99 tunneling project. It measures 57.2 feet (17.5 m) in diameter, which makes it the largest tunnel boring machine in history.

Bertha tunnel boring machine Mining Zimbabwe

Jan 23, 2020 Bertha was a 17.5 m diameter tunnel boring machine built specifically for the Washington State Department of Transportation’s (WSDOT) Alaskan Way Viaduct replacement tunnel project in Seattle. It was made by Hitachi Zosen Sakai Works in Osaka, Japan, and the machine’s assembly was completed in Seattle in June 2013. Tunnel boring began on July 30, 2013, with the machine

Gizmag goes inside the world's largest tunnel boring machine

Jul 23, 2013 On Saturday, a tunnel boring machine (TBM) so large that it looks like something out of Thunderbirds was dedicated in the city of Seattle. “Bertha,” as it’s known, is the world’s largest

Tunnel Boring Machine "Bertha" Successfully Completed SR

Tunnel Boring Machine "Bertha" Successfully Completed SR 99 Tunnel Project in Seattle Osaka, Japan, May 19, 2017—Hitachi Zosen Corporation(TYO:7004) has announced that the Tunnel Boring Machine (TBM) known as “Bertha” has successfully completed mining for the SR 99 Alaskan Way Viaduct Replacement Project in Seattle.

The World's Largest Tunnel-Boring Machine

Nov 11, 2013 In July, they unleashed Bertha, the world’s largest-diameter tunnel-boring machine. Built in Japan and reassembled in the U.S., Bertha is digging the 1.7-mile tunnel by advancing at an average

Seattle's 'Bertha' is a not-so-lean tunneling machine

Aug 19, 2013 Bertha was assembled in the 80-foot-deep pit and will displace 850,000 cubic yards of soil for the double-level, two-lane tunnel running between 60 and 200 feet below the ground.

'Bertha' to Start Digging to Replace Seattle's Alaskan Way

May 20, 2013 This summer, "Bertha," a 7,000-ton tunnel boring machine, is set to finally make that tunnel a reality when she starts clawing through dirt 80 feet

Bertha breaks through: Watch the tunnel boring machine’s

Apr 03, 2017 Follow Bertha, the SR 99 tunneling machine [WDOT] Bertha is drilling the last 100 feet of the SR 99 tunnel [CS] Foursquare Alaskan Way Viaduct. SR-99, Seattle, WA 98101 Visit Website.

Tunnel timeline: From conception to tunnel completion to

Dec 13, 2019 The tunneling machine known as Bertha is completely dissembled and removed from the receiving pit. December 2017 State transportation officials begin discussing what tolls will be implemented once

Dispute over missing evidence in Bertha breakdown goes to

Jan 10, 2019 January 09, 2019 at 5:17 pm PST By Graham Johnson, KIRO 7 News. Some pieces of the steel pipe the tunnel machine Bertha struck five years ago sat in a bucket Wednesday in a Thurston County courtroom.

The World's Largest Tunneling Machine Is (Finally) Getting

Mar 31, 2015 Bertha, the world’s largest tunneling machine, has been stuck under downtown Seattle since it broke in December 2013. Engineers have had to concoct a massive and expensive rescue plan

Seattle's Bertha Tunnel Project Plagued By Financial Woes

Jul 22, 2016 The world's largest tunneling machine, nicknamed "Bertha," is now working again, but the complicated fix of an underground breakdown in 2013

Bertha breaks through: SR 99 tunneling machine emerges

Apr 04, 2017 Background on tunneling machine repairs. Manufactured in Japan by Hitachi Zosen Corp., Bertha arrived in Seattle in April 2013. The machine was launched from a pit near the stadiums in July of that year. In December 2013, STP stopped mining after measuring increased temperatures in the machine.

Alaskan Way Viaduct Follow Bertha

Follow Bertha Thank you for following Bertha. The SR 99 tunneling machine, nicknamed Bertha, has completed her work. For the latest tunnel progress, visit our new tracker page. An abbreviated history of Bertha: