Hood Canal Bridge Demolition
description
Transcript of Hood Canal Bridge Demolition
East-half Replacement and West-half Retrofit ProjectTotal Project Budget: $471 millionContractor: Kiewit – General
Project Scope:• Replace the east-half floating portion of the bridge• Replace the east and west approach spans• Replace the east and west transition spans• Widen the west-half to allow for continuous eight-foot shoulders across the entire length of the bridge - matching the new east-half • Upgrade electrical systems on the west-half
Project Demolition:Pontoons R, S and T, left Port Gamble Bay on the Kitsap Peninsula at 8 a.m. Monday morning and were moored at Seattle’s Terminal 91 at 8 a.m.Tuesday morning. The pontoons traveled at a maximum speed of 2 knots, or about 2.3 mph from Port Gamble into Elliot Bay to Magnolia Bluff where they were moored at Terminal 91 in Seattle.
The replacement pontoons were originally built in the 1980’s
• Total Length of R, S, T: 3 Football fields Pontoon R: 360 feet long, 60 feet wide and 21 feet tall Pontoon S: 360 feet long, 60 feet wide and 21 feet tall Pontoon T: 180 feet long, 60 feet wide and 21 feet tall
• Total draft: 12 feet; 9 feet of the pontoons are above the surface of the water.• Weight of RST: 19,000 tons, more than five times the weight of the Space Needle (which is 3,700 tons).
Pontoons barged to Pier 91 in Seattle, carefully positioned along the inside pier.
Project completed on time, within budget and with zero accidents
Nuprecon LP was contracted for the demolition and removal of the old roadway and superstructure diagrams, to make way for the construction of a new, wider roadway on top of the 60-foot wide pontoons to match the height and width of the widened west-half. The refurbished pontoons will be towed back to Port Gamble this fall.
During the course of the contract, Nuprecon provided equipment and manpower to demolish and remove from the site 900 lf of superstructure including barriers, roadway slab, precast girders, girder stops and diaphragms located at Pier 91. Included in this work, Nuprecon will demolish 30 concrete columns and saw cut 900 lf of roadway deck. Girders and decking were picked with cranes and placed on flatbeds in 60’ sections and hauled through the City of Seattle to a local reclamation site.
Retrofitting these pontoons helped the Hood Canal Bridge Project meet its May-June 2009 float-in date and save money and time. If three more new pontoons had to be built, the project schedule would have increased by at least one year.
The new Hood Canal Bridge east-half will be comprised of 17 pontoons: R, S and T and 14 new pontoons constructed at Concrete Technology graving dock in Tacoma. The new Hood Canal Bridge east-half will be replaced during the six-week May-June 2009 bridge closure.
The Hood Canal Bridge is the longest floating bridge over saltwater in the world. WSDOT and K-G lead the world in floating bridge technology. Learn more about this exciting, one-of-a-kind project by visiting www.hoodcanalbridge.com. The site includes web cameras, media kits, animations, historical photos, fact sheets, towing information and community stories about the bridge.