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

2017-1-25  Washington State Department of Transportation 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

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

2019-5-24  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, Seattle's SR 99 Tunneling Machine, Is Finally Done

2017-4-5  The tunneling machine, named for former Seattle mayor Bertha Knight Landes, boasts a 57-foot diameter and measures 325 feet long. After dropping into a pit in July 2013, it started digging the...

Big Bertha: Mystery object blocks Seattle's tunnel drill

2013-12-17  Big Bertha: Mystery object blocks Seattle's tunnel drill Deep beneath Seattle, something has brought the world's biggest tunnel boring machine to an abrupt halt. The tunnel

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

2017-5-1  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 digger was tasked with the challenge of building a...

America's Biggest Tunnel-Boring Machine Is Stuck Beneath

2014-2-20  Bertha is part of a $3.1 billion plan to replace Seattle's aging Alaskan Way Viaduct with a bored tunnel, and the $80 million machine was going gangbusters at first, churning 30 feet per day...

Mystery of Seattle's Tunnel Borer Blockage Solved

2014-1-5  When it got stuck, big Bertha was only about 1,000 feet into a two-mile-long boring journey under Seattle for the tunnel that will replace the city's waterfront viaduct

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

2021-5-21  Paul figures Bertha put up five or six concrete rings that evening, extending the tunnel by another about 30 to 36 feet. Sometime the following morning, on

Contractor ordered to pay Washington state $57M over

2019-12-13  The tunneling machine Bertha breaks into daylight in 2017. A jury has awarded Washington state $57.2 million in damages over delays in the downtown

Big Bertha, the tunnel boring machine of Washington State

2016-9-19  Bertha is a tunnel boring machine built specifically for the Washington State Department of Transportation’s Alaskan Way Viaduct replacement tunnel project in Seattle. Bertha has to build the SR99 tunnel under downtown of Seattle, in order to replace the old viaduct “Alaskan Wayâ€. After some moments of pause for machine trouble

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

2019-5-24  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.

Watch Bertha, the world’s largest tunnel boring machine

2017-4-4  From the dark depths beneath Seattle, Bertha the SR 99 tunnel machine headed out of the muck and into daylight on Tuesday, completing a final push

America's Biggest Tunnel-Boring Machine Is Stuck Beneath

2014-2-20  Poor Bertha.North America's largest tunnel-boring machine, measuring 57.5 feet in diameter, hasn't moved more than 4 feet along its 1.7-mile route since Dec. 7. And she isn't going anywhere soon

Bertha breaks through: World's largest boring machine

2017-4-5  According to the WSDOT, Bertha's breakthrough is a good news/bad news event. On the one hand, a tunnel unique in the world has been dug, but it has a dirty big digging machine blocking it.

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

2021-5-21  Paul figures Bertha put up five or six concrete rings that evening, extending the tunnel by another about 30 to 36 feet. Sometime the following morning, on Wednesday, December 4, the operators began seeing 3- to 4-foot pieces of pipe and a bunch of smaller pieces showing up on the video feed of the conveyor belt.

Big Bertha Stuck: Differing Site Condition Principles

2014-1-30  Seattle Tunnel Partners (“STP”) has a contract with the Washington State Department of Transportation (“WSDOT”) to dig a two-mile long tunnel (using the world’s largest diameter tunneling machine) to replace the SR 99 viaduct. STP is a joint venture of Dragados USA, Inc.[i], based in New York, NY, and Tutor Perini Corporation, based in Sylmar,

Mystery of Seattle's Tunnel Borer Blockage Solved

2014-1-5  The Washington State Department of Transportation said Friday that the steel pipe that stopped Bertha, as the borer is nicknamed, on Dec. 6 is a 119-foot-long well casing installed in 2002 to

Trial begins in case of Bertha Seattle, Washington

2019-10-11  Trial begins in case of Bertha breakdown and Seattle's SR 99 tunnel construction delays A Thurston County jury is hearing arguments in the case that could put Washington

Seattle tunnel construction avoided Seattle, Washington

2019-1-18  Seattle used Bertha, the tunnel boring machine, to create the Highway 99 tunnel. Both tunnels were delayed and over-budget, but the numbers are significantly different. The Big

Big Bertha, the tunnel boring machine of Washington State

2016-9-19  Bertha is a tunnel boring machine built specifically for the Washington State Department of Transportation’s Alaskan Way Viaduct replacement tunnel project in Seattle. Bertha has to build the SR99 tunnel under downtown of Seattle, in order to replace the old viaduct “Alaskan Wayâ€. After some moments of pause for machine trouble

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

2019-5-24  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.

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

2021-5-21  Paul figures Bertha put up five or six concrete rings that evening, extending the tunnel by another about 30 to 36 feet. Sometime the following morning, on Wednesday, December 4, the operators began seeing 3- to 4-foot pieces of pipe and a bunch of smaller pieces showing up on the video feed of the conveyor belt.

Watch Bertha, the world’s largest tunnel boring machine

2017-4-4  From the dark depths beneath Seattle, Bertha the SR 99 tunnel machine headed out of the muck and into daylight on Tuesday, completing a final push

Big Bertha Is Digging Seattle's Massive Underground Freeway

2013-7-5  To do so, Seattle's using "Big Bertha:" the biggest Tunnel Boring Machine on Earth. Advertisement Built for the dig by Hitachi in Osaka Japan, the $80,000,000 Big Bertha

Bertha breaks through: World's largest boring machine

2017-4-5  According to the WSDOT, Bertha's breakthrough is a good news/bad news event. On the one hand, a tunnel unique in the world has been dug, but it has a dirty big digging machine blocking it.

Big Bertha Stuck: Differing Site Condition Principles

2014-1-30  Seattle Tunnel Partners (“STP”) has a contract with the Washington State Department of Transportation (“WSDOT”) to dig a two-mile long tunnel (using the world’s largest diameter tunneling machine) to replace the SR 99 viaduct. STP is a joint venture of Dragados USA, Inc.[i], based in New York, NY, and Tutor Perini Corporation, based in Sylmar,

Big Bertha and the Highway 99 Tunnel Project Emerald

Big Bertha uprooted 55 feet of the pipe on Dec 3, 2013. Right now the headlines have all changed. The headline of the Times Jan 17, 2014 was: “99 tunnel project’s director irked at state casting blame”. the article says that Seattle Partners project director Chris Dickson was surprised that the state blames them for the difficulties on

Trial begins in case of Bertha Seattle, Washington

2019-10-11  Trial begins in case of Bertha breakdown and Seattle's SR 99 tunnel construction delays A Thurston County jury is hearing arguments in the case that could put Washington

Big Bertha Lawsuits—Hitachi Zosen Weighs In ACS Lawyers

2018-1-17  In a recent article published by Seattle Business Magazine, the Japanese manufacturer of the much-maligned tunnel machine (nicknamed “Bertha”) provided its version of events and its position to the public. The interview took place after executives from Hitachi Zosen were not invited to the ceremony celebrating Bertha’s breakthrough at the end of its two-mile journey