Post by Elaine Heast on Jul 31, 2013 14:46:34 GMT -8
On July 30th the worlds largest tunneling machine, affectionately named Bertha, started her long trek beneath downtown Seattle. Bertha is drilling the two mile path for the new Alaskan way viaduct and is expected to emerge in again in 14 months. Initially she will progress 6.5ft per day with up 20ft per day once she's at full speed, around Yesler way. Berth will pass through roughly 8 kinds of soil along her way as she bores up to 200 feet under the ground and passes beneath other tunnels and structures. Strategic buildings along the route have been equipped with a network of 36 lasers to monitor vibrations and structural movement to ensure there is no damage once she gets up to speed. The tunnel is expected to open for drivers in 2016.
You can find out more about Bertha and track her movements on the WSDOT Alaskan Way Viaduct project page.
You can find out more about Bertha and track her movements on the WSDOT Alaskan Way Viaduct project page.
