TNC is using LGH electric winches and come-a-longs to erect a new suspension bridge, which is being built parallel to and south of the existing 1950s Narrows Bridge on State Route 16.
LGH said the new bridge will help alleviate congestion, improve driver conformability and increase safety for drivers as they travel along the State Route 16 corridor.
Currently, 85 to 90,000 vehicles use the corridor on a daily basis, but the bridge is only designed to handle approximately 60,000 per day. Officials estimate that the use of the freeway will increase to 120,000 vehicles per day by 2020, which prompted the building of the additional bridge.
According to Tony Fiscelli, general manager of LGH’s US corporate headquarters, located in Bridgeview, Illinois, the electric winches are being used to inch large gantries along giant spun cables that support a 710,000lb I-Beam on the new bridge. He said: “A giant barge carries all of the deck sections to the place where they will be erected on the bridge.” He added: “Strand jacks are being used to lift the bridge deck pieces from these barges into their final location on the main cable. Our come-a-longs are then used to inch the deck plates closer before they are settled into their final positions.”
Erin Hunter, of TNC, said the new bridge will give eastbound commuters two general purpose lanes, an HOV lane, and a “drop” lane by summer 2007. In summer 2008, both new and existing bridges will be open in their final form and will allow the existing bridge to handle westbound traffic on two general purpose lanes with one carpool lane. The new bridge will then be able to handle eastbound traffic with two general purpose lanes, one HOV lane and a fourth “drop” lane, beginning at the 24th Street eastbound on-ramp in Gig Harbor and ending at the Jackson Street off-ramp in Tacoma.
The first Tacoma Narrows Bridge opened on July 1 1940, only to collapse in a wind-storm several months later on November 7. “Galloping Gertie”, as the bridge was known, became famous as “the most dramatic failure in bridge engineering history”. A new and, according to LGH, “much safer” Tacoma Narrows Bridge opened on October 14 1950 and is the fifth longest suspension bridge in the US.
