Ultra-thin whitetopping (UTW) for general aviation airports in New Mexico

648015777Final report; June 1999-Dec. 2001.PDFTech ReportNM01MSC-03CO 3751Overlays (Pavements)WhitetoppingAirport runwaysNew MexicoNew Mexico. Dept. of TransportationLenke, Larry R.McKeen, R. GordonUniversity of New Mexico. ATR InstituteNew Mexico. Dept. of Transportation. Research BureauNTL-HIGHWAY/ROAD TRANSPORTATION-Pavement Management and PerformanceNTL-HIGHWAY/ROAD TRANSPORTATION-MaterialsNTL-AVIATION-Airports and FacilitiesUS Transportation CollectionWhitetopping is a pavement rehabilitation construction practice where portland cement concrete (PCC) is placed over an existing asphalt concrete pavement as an overlay. Ultra-thin whitetopping (UTW) is generally a thin overlay with a thickness between 2 and 4 inches. UTW is usually of high strength and made with fibers for improved tensile strength, ductility and enhanced fatigue life. UTW differs from conventional whitetopping because of the design and construction procedures that ensure substantial bonding between the UTW and the underlying asphalt. UTW also employs much closer joint spacing than conventional whitetopping; this reduces the load-induced stresses within the UTW. UTW does not make use of steel reinforcement. A literature and technology review found that UTW is a proven means of asphalt pavement rehabilitation for improved serviceability. The mechanistic design concepts for UTW are clearly established. The construction methodologies have been developed and are in place. The material technology for fiber reinforced high strength PCC is available. Specifications have been written and successfully used on numerous highwayand airport pavement projects. The initial cost of UTW is more than the common asphalt concrete pavement rehabilitation used in New Mexico. However, life cycle costs of UTW compared to asphalt overlays are considered competitive. It is recommended thatthe NMSHTD design and construct UTW test sections at an appropriate selected airport in the state of New Mexico. Such a project will allow for the determination of the relative initial costs of the UTW versus asphalt rehabilitation, and long term monitoring will allow for the determination of the life cycle costs and long-term performance of UTW versus asphalt