The Bellevue Direct Access project was an accelerated bridge construction project utilizing precast columns, slabs, and W girders to construct on/off ramps and an overpass over I-405 at NE 4th Street in Bellevue Washington. The on/off ramps were constructed using precast prestressed columns and slabs, with cast in place cross beams and decks. The two span NE 4th St. bridge over I-405 was framed with W58MG girders and precast prestressed Stay in Place slabs to form the cast in place deck.
Just to note, the “M” in the W58MG girder name designates that these girders are metric. This project was made during a time when there was an attempt to switch to the metric system. Today we would simply call this girder a W58G.
Accelerated Construction – The precast columns and slabs allowed for the accelerated construction of the on/off ramps. The stay-in-place slabs also contributed to the accelerated construction of the bridge deck.
Precast Prestressed Girders – 40 (ea), W58MG Girders, 105’-1” – 114’-1 ¼”
Precast Prestressed Stay in Place Slabs – 418 (ea), SIP Panels, 3 ½” Thick, 4’-5 ¼” Wide, 5’-5 ¼” to 8’ Long
Precast Prestressed Slabs – 134 (ea) PC/PC Slabs, 11” thick, 5’-7 ¼” Wide, 23’-7 ½” – 25’-10 ¼” Long
Precast Prestressed Columns – 62 (ea) Columns, 2’ X 2’-8”, 7’-6 ¾” to 35’-6 ¾” Long
