This special report describes the accelerated pavement testing of ultra-thin whitetopping (UTW) undertaken by the Federal Highway Administration at their accelerated loading facility (ALF) in McLean, Virginia. The UTW pavement sections were placed in 1998 atop existing asphalt sections that had been previously loaded by the ALF. The eight pavement sections were loaded by the facility, and five of the eight lanes showed little or no distress as a result. Conclusions indicate that the load carrying capacity of UTW is sufficient for its intended uses, including streets, local roadways, general aviation pavements, bus lanes, turning lanes, and ramps.

Available for $5. Link goes to bookstore page, search by product code. This report, produced by the Federal Highway Administration (FHWA), presents the latest information on the design, construction, and performance of portland cement concrete (PCC) overlays. Bonded, unbonded, whitetopping, and ultra-thin whitetopping overlays are covered in this synthesis of the current state of the technology. This comprehensive book is a must-have for those interested in concrete pavement overlay design and construction.

This document is available for $6 from American Concrete Pavement Association, search by product code at bookstore. This semi-technical brochure outlines the requirements and steps to repairing ultra-thin whitetopping overlays. Full-color photographs visually demonstrate each step.

This document is available for $25 from the American Concrete Pavement Association, search by product code. Best-selling engineering manual includes comprehensive coverage of all aspects of concrete overlays on existing asphalt pavement. It includes information on the benefits, history, performance, design practices, and construction of all types of whitetopping. A special chapter discusses Ultra-Thin Whitetopping (UTW), including an interim procedure for determining the load-carrying capacity of UTW based on research and performance surveys.

Available for free. This 2-page case study highlights the reconstruction of a deteriorated asphalt street in Sheridan, WY. The process included the use of full-depth reclamation (FDR) with cement for the base and ultra-thin whitetoppping (UTW) for the surface. Pavement design called for 3-1/2 inches of UTW with control joints sawn in a four-foot grid over eight inches of an FDR base. Tests performed after construction showed the cement-stabilized FDR base with a 28-day compressive strength of 320 psi and a 28-day concrete compressive strength of 5,250 psi. After a year of traffic, the reconstructed street is performing well, and the city is pleased with the results.

Industry resource for ready mixed concrete.

This report presents the results of solar reflectance testing on 135 concrete specimens from 45 concrete mixes, representing a broad range of concretes. This testing determined which combinations of concrete constituents meet the solar reflectance index requirements in the Leadership in Energy and Environmental Design for New Construction (LEED-NC) Sustainable Sites credit for reducing the heat island effect. All concretes in this study had average solar reflectances of at least 0.30 (corresponding to an SRI of at least 29), and therefore meet the requirements of LEED-NC SS 7.1. These concretes also meet the requirements for steep-sloped roofs in LEED-NC SS 7.2. The lowest solar reflectances were from concretes composed of dark gray fly ash. The solar reflectance of the cement had more effect on the solar reflectance of the concrete than any other constituent material. The solar reflectance of the supplementary cementitious material had the second greatest effect.