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Posts Tagged ‘Seattle’

Seattle, WA: Fly Through the Entire SR 99 Tunnel

Tuesday, October 24th, 2017

Now that the tunneling machine Bertha’s work is complete, it’s possible to fly a drone with a video camera from end-to-end inside Seattle’s SR 99 tunnel. In two minutes, you’ll see two miles of ongoing construction work. The upper roadway of the tunnel’s double-deck highway is more than 85% complete. Up next? Installation of the lower roadway, and all the systems it takes to operate a modern tunnel.

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2017 ACEC Grand Conceptor Award Winner: SR 520 Floating Bridge in Seattle, Washington

Monday, May 8th, 2017

The ACEC 2017 Engineering Excellence Awards “Grand Conceptor” Winner: SR 520 Floating Bridge Seattle, Washington Designed by HDR.

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Seattle, WA: SR 520 Floating Bridge Documentary

Friday, April 28th, 2017

This short documentary tells the story of the new floating bridge across Lake Washington in Seattle, Washington. The bridge was a project of the SR 520 Bridge Replacement and HOV Program and opened to traffic in April 2016.

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Seattle, WA: Bertha Breaks Through

Friday, April 7th, 2017

The SR 99 tunneling machine, Bertha, breaks through to daylight on April 4, 2017 near Seattle’s iconic Space Needle after tunneling 1.7 miles underneath downtown Seattle. See what one of the world’s largest tunneling machines looks like up close as only a drone can show.

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WSDOT: Building a Highway Underneath Seattle

Tuesday, December 20th, 2016

With a time-lapse camera mounted 54-feet high, you almost get a bird’s-eye view of work inside Seattle’s SR 99 tunnel. As the tunneling machine Bertha builds the tunnel, road crews are right behind – building the foundations, walls and the top deck of the double-deck highway drivers will travel on when the tunnel opens. Take a look.

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Behind the Scenes of Seattle-Tacoma International Airport’s People Mover System

Thursday, December 15th, 2016
Below ground, one of the trains arrives at SEA

Written by David Parker Brown, Editor-in-Chief and Founder of Airline Reporter The Seattle-Tacoma International Airport (SEA) has been my home airport most of my life. I have seen the many changes over the years and I am proud to call it mine. Growing up, I lived in Oak Harbor, WA (about 90min northwest of Seattle) […]

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Impacts of Carsharing in Five North American Cities

Wednesday, July 27th, 2016
Table 1 Vehicle and GHG Impacts from Free-Floating One-Way Carsharing

TRANSPORTATION SUSTAINABILITY RESEARCH CENTER Impacts of Car2Go on Vehicle Ownership, Modal Shift, Vehicle Miles Traveled, and Greenhouse Gas Emissions: An Analysis of Five North American Cities Executive Summary Carsharing is the shared use of a vehicle fleet by members for tripmaking on a per trip basis. There are four forms of carsharing in North America today: […]

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Seattle, WA: Workers Inside the SR 99 Tunneling Machine

Tuesday, July 5th, 2016

This video was provided by Ballard Marine Construction, the firm in charge of managing and performing hyperbaric work on the SR 99 Tunnel Project in Seattle. It shows crews at work behind the SR 99 tunneling machine’s cutterhead during a planned maintenance stop in spring 2016. To stabilize soil and water that would otherwise flow through openings in the cutterhead, crews must pump compressed air into their work space at the front end of the machine.

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Seattle, WA: Tunneling Under the Alaskan Way Viaduct

Tuesday, May 10th, 2016

After nearly a week of tunneling under the Alaskan Way Viaduct, crews are steadily continuing Bertha’s underground drive towards downtown Seattle. This video gives you a behind-the-scenes glimpse into how the new tunnel is being built, showcasing the complex operations involved in this project. Massive concrete ring segments are transported to Bertha’s segment erector where they are lifted into place, allowing the machine to push forward while the excavated soil is transported along a network of conveyer belts and into a barge moored at Elliott Bay’s Pier 46.

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Seattle, WA: The Part of the Tunnel Built WITHOUT Bertha

Thursday, December 31st, 2015

Approximately 20 percent of the SR 99 tunnel was designed to be built without Bertha, the SR 99 tunneling machine. Seattle Tunnel Partners bored more than 1,000 feet of tunnel before they stopped to repair Bertha. Since then, they have built an additional 1,200 feet of tunnel using cut-and-cover tunnel construction. This video gives a close-up look inside the newest part of the project to learn more about the tunnel built without Bertha.

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