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 tunnel large enough to carry four lanes of motor traffic under the heart of Seattle.
Apr 03, 2017 · Bertha, one of the world's largest tunnel boring machines, emerged north of downtown Seattle on Tuesday.
The "Big" in Bertha's name isn't there for the catchiness. It's there because it's apt. With a 57-foot diameter and a length of a football field, Big Bertha is the world's largest tunnel-boring machine.
Bertha, the world's largest tunnel-boring machine, ends its journey today. It has spent four years traveling less than two miles to build a new car tunnel underneath Seattle.
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 Blackstone reports on what the high-tech machinery can do, as well as its latest challenge digging in the depths of Seattle.
A tunnel boring machine ... An earth pressure balance TBM known as Bertha with a bore diameter of 17.45 metres ... The world's largest hard rock TBM, ...
Dec 24, 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...
Jul 22, 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 digger was ...
The normally sedate city of Seattle sounded more like the set of a science fiction epic today as the world's largest boring machine roared and screeched its way into the open air. The tunnel boring machine, better known as "Bertha" cut through a wall of reinforced concrete in the shadow of the city ...
Contractors building a highway tunnel under Seattle are preparing to remove the world's largest boring machine so that it can be repaired. The gigantic drill, known as Bertha, stopped working in December 2013 after digging just 1,000ft of its two-mile journey to replace the aging Alaska Way, which was damaged in 2001 by an earthquake.
SEATTLE — The world's largest tunnel-boring machine broke through a concrete wall beneath Seattle on Tuesday to reach the end of its long, troubled journey, a milestone in a multibillion-dollar project to replace an aging highway hugging the city's waterfront.
Bertha was designed and manufactured by Hitachi Zosen Sakai Works of Osaka, Japan, and is the world's largest earth pressure balance tunnel boring machine, at a cutterhead diameter of 57.5 feet (17.5 m) across.
The world's largest tunnel-boring machine, nicknamed Bertha, has been stuck beneath Seattle for over a year amid its efforts to build a pathway for an underground highway to replace one that is currently obstructing the city's waterfront.
A worker enters the tunnel dug by Bertha, a tunnel-boring machine, that has seen major delays, last week in Seattle. (David Ryder / New York Times News Service) 2732525
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 in a years-long effort to create space for a new highway beneath the city.
The tunneling machine known as Bertha began tunneling beneath Seattle in July 2013 (photo at right: ... + Bertha's tunnel route
The world's largest tunnel-boring machine has stalled deep beneath Seattle. There's only one way to finish the project. Bertha must be saved...
Bertha, the world's biggest tunnel-boring machine currently underneath Seattle, has been stuck for nearly one month. Now, crews are close to figuring out what exactly is stopping her.
The World's Largest Tunnel-Boring Machine Must Be Saved. Bertha has stalled deep beneath Seattle, leaving the city's planned waterfront renaissance hanging in the balance.
Bertha breaks through: World's largest tunnel-boring machine which is building a $3.1billion underground highway beneath Seattle completes mission three years late
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 of 35 feet a day.
Seattle's Big Bertha Tunneling Machine Is Finally Back on Track. ... Now the Seattle tunnel boring machine is finally back on track.
Last year, a Japanese company began assembling "Bertha," the tunnel-boring machine that will slice through the earth to make room for the underground roadway.