WAFFLEMAT REPAIRS FOUNDATIONS IN 20 BUILDINGS
Hickam AFB on the Island of Oahu is currently HQ for the US Pacific Air Force, and houses the 15th Airlift Wing, Hawaii Air National Guard’s 154 Wing, as well as the 515 Air Mobility Command. Built during the 1930’s, many of the homes and buildings located on base have experienced significant foundation settlement over the years (as much as 7 inches), and today approximately 450 of them are in need of some level of renovation.
To make the project more interesting, the buildings were included in the US National Register of Historic Places and US National Landmark District in 1985. This means any work on the foundations has to be performed from the inside, without tearing down any walls. Also, the soils are highly expansive as well as contaminated, so work and removal on that portion alone could cost $15 – $20 per sf.
After nearly two years of investigation, the repair contractor chose Wafflemat to replace foundations on 45 of the 450 buildings designated as requiring ‘major’ foundation re-construction. Initial projections using a conventional foundation required removal of between 3 – 4 feet of existing soils, and then importing the same amount of expensive select fill. In addition, this scenario included managing the contaminated off-haul, which necessitates treatments such as burying/capping in pits or, worse, burning. In every case it’s an expensive, and time-consuming process, as remember, all this must be done in ‘close quarters,’ much by hand and small tools, as the historic walls cannot be demolished.
Use of Wafflemat was vastly easier and significantly less expensive, as excavation was only 8.5″ (the height of the Wafflebox) instead of the 3 – 4 feet. In addition, the voids under the individual Waffleboxes and ribbed design provides for superior performance in expansive soils. The project’s design manager remarked: ‘There’s no way we could have done this anywhere close to budget without Wafflemat. The export and import of the soils alone would have been many times more expensive, and we would still face the issue of what to do with the contaminated off-haul. Our mission here is to give young families a beautiful house at Hickam. Wafflemat provides the foundation for those homes that required the most extensive repairs, so we could deliver the homes we promised.’
Below, you’ll see the various stages of construction; work through windows/doorways, leveling the ground (remember, only 8.5″ vs. 3 – 4 feet for the alternative foundation system), installing Wafflemat, and the new steel framing. This is not only an incredible W/matt reference, but considering the location, historical significance, and construction elements/intricacies involved, a wonderful success story in general.