An unknown object that fascinated the country last month when it stopped the world’s most powerful tunnel boring machine digging underneath Seattle has finally been identified.
The tunneling machine known as Bertha began tunneling beneath Seattle in July 2013 (photo at right: the machine's cutterhead being lowered into the launch pit near Seattle's stadiums). The machine completed its tunneling on April 4, 2017 and was fully dismantled and removed from the tunnel on Aug. 23, 2017.
Now the Seattle tunnel boring machine is finally back on track. It just broken through an access repair tunnel and has since mined 73 feet since December 22. ... Fortunately, the machine had not ...
Why Seattle's Huge Tunnel-Boring Machine Is Still Stuck A year after Bertha got stuck, plans to free the big machine have stalled. And there's another problem.
Inslee orders tunnel dig halted as soil sinks above Bertha ... (Ken Lambert / The Seattle Times) ... The world’s largest boring machine is currently stopped just north of Main Street.
The world’s largest tunnel-boring machine is on schedule to break into daylight this spring after a tumultuous dig under downtown Seattle that’s years behind schedule.
4/4/2017 · Workers look on as the machine head of Bertha, the world's largest tunnel-boring machine, is lifted from an access pit for repairs in Seattle, Washington March 30, 2015.
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 ...
August 2017: Final piece of dismantled machine removed While Bertha was underground, this page tracked her progress beneath Seattle. With the machine dismantled and removed, we are now tracking tunnel progress on a new page.
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