I-405/SR 518 Concrete Pavement Rehabilitation
Decades of heavy use on both the I-405/SR 518 freeways resulted in severe cracks, bumps, and ruts. Replacing damaged and broken panels, repaving sections, and grinding existing panels created a smoother drive with better traction and new high visibility striping provided better visibility for drivers.
Atkinson's scope of work included the replacement of concrete pavement in all four lanes of northbound I-405 from SE 8th Street to just north of Main Street in Bellevue. In addition, crews ground the existing pavement across all lanes and replaced an additional 82 failing concrete panels on northbound I-405 just south of SE 8th Street and from Main Street to SR 520. Work also featured HMA paving of the inside/outside shoulders, and installing traffic loops, striping and drainage improvements, including catch basins with and pipe installation in the median and at the northwest approach slab of the SE 8th Street Bridge. The project team also improved nearly a mile of SR 518 pavement between I-5 and Sea-Tac Airport by replacing more than 50 concrete panels and using a diamond grinder to smooth out bumps and ruts on other areas of the highway. This included replacing data loops and updated striping on SR 518.
To minimize impacts to the traveling public, a majority of the work on I-405 was performed during two 54-hour weekend closures of NB I-405 and on SR 518, crews used extended weekend lane closures to complete the work. During each I-405 closure, crews demolished two lanes (~3,600 lineal feet long) of the existing PCCP pavement, removed unsuitable materials, placed and compacted subgrade materials, placed asphalt pavement underlayment and joint dowel bars, and repaved PCCP roadway sections. Quantities totaled 6,288 cubic yards of PCCP concrete paving, 5,059 tons of HMA asphalt paving, 16,280 square yards (rough grade) and 4,687 tons (fine grade) of CSBC.