50% cost and 70% time savings for the airforce one airfield as a result of uretek ground improvement
Andrews Air Force Base is the home to Air Force One. The plane’s ability to land is challenged when “ramp freezes” occur, shutting down operations due to security reasons. Every airport repair job needs to be completed quickly, but Andrews required even faster repair which only URETEK could provide.
A significant dip had developed in one of the runways at Andrews Air Force Base. An engineering investigation concluded the dip was caused by a leaking pipe. The soils around the pipe were weakened to the point that full-depth reconstruction of the panels above it appeared to be the only option.
The URETEK ground improvement solution relies on a two-part geopolymer system injected beneath the concrete through pre-drilled 15mm holes. The polymerization between the soil and the slab yields a co-efficient of expansion of 20 to 1, and a lifting capacity gf 8,000 pounds per square foot. The URETEK ground improvement solution was also used in this project to add density to the soils at depth by injecting the geopolymer below the soil-pavement interface. URETEK performed several tasks in a short time frame. First, they employed the URETEK re-levelling solution to bring the panels in the dipped area to profile.
The crew then re-constituted the soils around the pipe with the ground improvement solution. Using a grid pattern, the geopolymer was injected at depth, working inwards towards the pipe to squeeze the water out of the soil and into the pipe. Sealing the leaky joints of the pipe was the next step before routing and sealing the pavement on the surface.
To excavate and replace the area of concern would have cost approximately USD $250,000 with a crew on-site working for 35 days. URETEK’s repair strategy cost half the replacement estimate and took a total of 10 days to execute. Due to the interruption of the ramp freezes, crews worked mostly at night, keeping traffic rolling during peak hours.