Scheduled to open in December 1993, Denver's new $2.7-billion International Airport will be the nation's second largest public works project.
Design of the subgrade and pavement for runways, taxiways, and aprons consists of 5 feet of select, compacted subgrade topped with 1 foot of stabilized subgrade, an 8-inch layer of cement-treated base, and 17 inches of portland cement concrete. To boost pavement life from 20 to 40 years, engineers added 1 inch of concrete to the thickness required by the FAA's design chart. A thicker pavement adds "wear and tear" resistance and load-carrying ability.
In areas for slower moving aircraft, transverse dowel bars are being installed for load transfer under sawed joints for controlled cracking. At runway midsections, where aircraft land and take off, loads are more dynamic than static, so transverse steel is not used. Instead, aggregate in the concrete is sufficient to carry loads across sawed joints.