BOEING FRICTION STIR WELDER FOUNDATION SLAB
Project: Boeing Friction Stir Welder Foundation Slab
Where: St. Louis, Missouri
When: September 2005
Size: 200 Cubic Yards
Engineer: Jacobs Engineering, Aviation Division
Concrete Contractor: McCarthy Construction
Concrete Supplier: Metro Materials
Product Used: Komponent®
Boeing Production Facilities needed an extremely stable, flat, crack-free, and joint-free surface to operate a large, heavy precision Friction Stir Welder. Type-K Shrinkage-Compensating Concrete was specified for the upper two feet thickness of the 32' by 86' foundation slab. The slab included bearing areas, heavy I-beams cast into the concrete, and recessed areas. A monolithic placement and a super-flat surface were specified for this foundation slab in a high bay pre-engineered metal building.
After reviewing the job conditions and procedures using Type-K, McCarthy, Metro Materials, and CTS Cement determined that Komponent™ would produce the best results. Komponent™ was used to replace 15% of the portland cement in the mix design and then the mix was tested using local aggregates and portland cement. Boeing agreed to use Komponent™ because the 14-day results showed that the Komponent™ performance was equal to the Type-K cement mixes they used on previous jobs. The other benefit is that the Komponent™ costs less than Type-K Cement.
The Komponent™ was blown into a silo at the ready-mix plant and the batching and mixing proceeded as usual. The resulting concrete had a .48 w/c ratio and was consistently at or near an 8" slump for each load. A concrete boom pump was used for conveyance. The placement started at 6:00 a.m., was completed by 9:00 a.m., finishing was completed by 1:45 p.m., and pre-soaked burlene was immediately placed on the slab. The soaker hoses that kept the burlene wet for seven days did not interfere with on-going construction activities.
Boeing got the stable, flat, crack-free, and joint-free foundation slab that they needed.
More Information on System-K™ here