Setting the Voided Slabs

< Pouring Piers 14. 15. and 16 | Building the New Bridge | Pouring the East and West Abutments >

On Sunday, February 12th, the American Construction barge Dungeness was brought up from Tacoma loaded with 76 of the 96 voided slabs that will make up the deck of our new bridge. The 20 that were left at Concrete Technology Corporation in Tacoma (the fabricator) are for the north side of the new deck that will be installed when the old bridge is removed. The barge Valor was anchored on the north end of Stretch Island until it was needed again.

On Monday, February 13th, the American Construction crew started setting the voided slabs onto the new bridge substructure. These pre-stressed concrete slabs are 4 feet wide, 51 feet long, and 18 inches thick and weigh approximately 20 tons each. The voided slabs are placed between the new piers to form the substructure for the main concrete driving deck of the bridge. They are called voided slabs because three 9-inch-diameter tubes or “voids” run longitudinally down the center of each slab to reduce the weight.

When the bridge is complete, there will be 6 slabs placed side by side between each set of piers.

At this time, American Construction is setting 3 slabs wide between Pier 1 through Pier 3, 4 slabs wide between Pier 3 through Pier 5, and 5 slabs wide between Piers 5 through Pier 17.

The south driving lane on the new bridge will be limited to approximately 10.5 feet wide on the west end until the existing bridge is removed and the new bridge is finished.

The green rebar you see on the south side of the slab is part of the support structure for the curb.

One of the pre-stressed concrete slabs installed between Pier 5 and Pier 6

Two of the pre-stressed concrete slabs installed between Pier 3 and Pier 4 

< Pouring Piers 14. 15. and 16 | Building the New Bridge | Pouring the East and West Abutments >