Maybe the restart of the world’s largest tunnel-boring machine will come as a Christmas present to the folks in Seattle, as the scheduled boring by “Bertha,” the 57.5-ft-dia machine currently sitting idle under downtown
Portland's troubled Morrison Bridge, which spans the Willamette River, will receive its third deck in four years after Multnomah County engineers settled on an open-grid steel deck with a 2.5-in. layer of lightweight concrete to replace a faulty polymer decking system.
The nation's longest non-vehicular multi-modal bridge, set to open on Sept. 12 across Portland, Ore.'s Willamette River, elevated risk management to a priority early on to help crews overcome unexpected site conditions.
Sound Transit Crews install rebar at the Capitol Hill Station pedestrian tunnel, which lies beneath Broadway and connects to Seattle Central Community College. Related Links: Seattle Rail Tunnels Proceeding Smoothly Glen Frank: A Wrestler Leads Tough Tunnel Job As crews in July removed a wall that separated existing rail track from the construction zone for a segment of the light-rail system that will connect downtown Seattle to the University of Washington’s Husky Stadium, the nearly $2-billion project, which includes two underground stations and 3.15 miles of bored track, remains about six months ahead of schedule six years into construction. The
Enlarge Photo Courtesy of WSDOT Steel reinforcements are being added to TBM Bertha in hopes of avoiding getting stuck again. Enlarge Photo Courtesy of WSDOT Big TBM awaits resumption of excavation on Alaskan Way Viaduct replacement project. Related Links: Mammoet Custom Gantry Brings Up Bertha for Repairs Seattle Tunneling Behemoth Bertha Awaits Repairs to Bearing Seals The wait for one of the world's largest tunnel-boring machines to resume excavation under downtown Seattle should come to an end in late November, according to a new schedule released by contractor Seattle Tunnel Partners (STP).Dubbed "Bertha," the TBM has sat idle since December
Related Links: Washington State Pulls the Plug on Advisory Panel Shocked and disappointed: That's how Patricia Galloway, chair of the three-member expert review panel for Washington state's $2-billion Highway 99 bored-tunnel project, described the panel's scrapping by state lawmakers.State legislators apparently perceived the panel as a legal risk and wanted to retain a clear distinction between the roles of the state and the contractor, avoiding any appearance that the state-named panel was providing recommendations to the contractor. Neither the Washington State Joint Transportation Committee, which appointed the panel, nor its coordinator would comment beyond confirming the panel's demise.It remains a
Photo Courtesy of Washington State Dept. of Transportation Much like a gigantic tooth extraction, Mammoet's lifting device pulled up Bertha's cutterhead. Related Links: At Last, Highway 99 TBM Rescued in Seattle Lifting Bertha, the Worlds Largest Tunnel Boring Machine Engineers never planned to lift "Bertha"—at 57.5 ft in dia, the world's largest active tunnel-boring machine—out of its bored tunnel. But when it came time to remove for repair her 2,000-ton cutter-drive unit from 120 ft below downtown Seattle, heavy-lift specialist Mammoet created a custom gantry system for the job.Due to the site constraints and soft waterfront soil conditions, Mammoet didn't
Photo Courtesy of Washington State DOT After 15 months of sitting stuck under the city, TBM Bertha has been rescued. Related Links: Divers Searching for Way To Get TBM 'Bertha' Moving Again Sinking Soils Further Impede Efforts To Extricate Alaskan Way Viaduct's Stuck TBM After sitting virtually stalled in her tracks for more than a year, Bertha, North America's largest-diameter tunnel boring machine (TBM), has finally been rescued. Before she can begin excavating again, contractor Seattle Tunnel Partners (STP) must open up the 57.5-ft-dia cutter head to see how extensive repairs need to be.Bertha had sat under downtown Seattle since
Photo Courtesy of Sundt-Slayden A bridge job employs prefabricated arches and nitrogen-cooled concrete. Photo Courtesy of Sundt-Slayden Related Links: Truss Travels On Teflon-Coated Track Prefabricated steel arches, liquid nitrogen-cooled concrete and two perched box caisson river piers are facilitating the construction of a new $307.5-million Sellwood Bridge in Portland, Ore.—the largest project of its kind in the history of Multnomah County.In 2013, crews with the Sundt-Slayden joint venture contractor moved a 1,100-ft-long truss span 66 ft north to serve as a temporary detour over the Willamette River. Since then, other techniques have kept the team busy. Crews are currently erecting
Photo Courtesy Sprague Theobald Russian trawler near Greenland finds ample open water in a formerly ice-bound channel. Video by Sprague Theobald Related Links: Foss Maritime The Port of Seattle this winter has been locked in a discussion about oil drilling in the Arctic after approving a short-term lease with Foss Maritime, whose clients include Royal Dutch Shell PLC, to use part of Terminal 5 to stage marine vessels.The agreement with Foss opens up the port to housing ships planned for Arctic oil-drilling exploration, environmental groups say.THEOBALDSprague Theobald, a two-time Emmy award-winning documentary filmmaker and expert sailor, has voyaged through the
