The project involves the repair and replacement of a large section of seawall along Seattle's downtown waterfront, a popular tourist area.
The wall, which was built between 1911 and 1936, has deteriorated over time, making it vulnerable to storm and earthquake damage.
Keller will use jet grouting technology to construct a grid of approximately 5,500 large-diameter soilcrete columns at depths of up to 26m, to provide seismic stability and foundation support for the new seawall. The project involves working around existing timber piles and so Keller will employ a surveying process that allows it to identify obstructions and revise the grid pattern as the work proceeds.
A test programme is expected to begin in March, following which the work will be carried out over three years, avoiding the main periods for tourism.
Keller chief executive Justin Atkinson said: "At Elliott Bay, the particular challenges associated with constructing jet grouted columns around existing timber piles add complexity to this contract, which plays to our strengths.鈥
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