At 12:45 p.m. yesterday, Texas-based hauler Big Boat Movers arrived at the Washington/Idaho border with the second of two 100-ton expansion joints for the new Tacoma Narrows Bridge, according to the Washington State Department of Transportation. Washington State Patrol officers will perform a routine safety inspection on the 148-foot-long, 14.6-foot-wide, 18-axle truck. Once the truck passes the safety inspection, the truck will move to WSDOTs Pines Road maintenance facility about 12 miles away.
The expansion joint will remain on Big Boats equipment through the weekend. On Mon., April 23, Tacoma-based hauler Omega-Morgan Rigging & Industrial Contracting is scheduled to arrive at the maintenance facility and transfer the expansion joint onto their equipment. The transfer will reconfigure the load to a 17-axle, 17.4 foot-wide, 200-foot-long truck, creating a load-to-axle ratio that conforms to Washington State law.
Omega-Morgan moved the first expansion joint across Washington state last week. Hired by joint fabricator D.S. Brown of Minnesota, Omega-Morgan took over the job after Big Boat Movers faced obstacles in configuring the load to meet state permit standards.
Omega-Morgans crew plans to use several days to traverse the state, and they will follow the same procedures and route that were used during the first move. As with the first expansion joint, WSDOT will attach a GPS unit to a pilot car accompanying the massive load. Allowable travel times for the load vary across the state depending on topography and population density. In the most densely-populated areas around greater Seattle, the hauler is allowed to travel only during late night hours. Throughout the journey, the truck will be accompanied by pilot cars and, at times, by Washington State Patrol troopers.
Since the truck will use two lanes along its journey, motorists are advised to expect delays and to monitor the trucks progress by visiting http://www.wsdot.wa.gov/projects/sr16narrowsbridge/ .
The specific route will be as follows: I-90 to Bellevue, I-405 to Tukwila, I-5 to Tacoma, and SR 16 to the Tacoma Narrows Bridge. Since this second expansion joint will be installed on the east end of the bridge, the hauler will not travel across the existing Tacoma Narrows Bridge. Instead, the truck will exit westbound SR 16 at Jackson Avenue, travel over the Jackson overpass, and use the eastbound Jackson exit to access the east anchorage area. The eastbound Jackson exit will be closed to traffic during delivery.
The expansion joints consist of rows of steel joined with neoprene strip seals. Each expansion joint weighs 100 tons, and measures 70 feet long by 15 feet wide. Acting like accordions, they are designed to absorb up to 56 inches each of deck expansion and contraction that can be caused by thermal changes, wind forces, traffic movement or seismic motion. They were fabricated specifically for this bridge by the D.S. Brown Company. The two massive expansion joints will sandwich the mile-long steel deck.
