PAVEMENT CONDITION SURVEYS OF ULTRATHIN WHITETOPPING PROJECTS

Abstract

Ultrathin Whitetopping (UTW) has emerged as a promising technique for rehabilitating asphalt pavements by overlaying them with concrete layers of 50 mm to 100 mm thickness. This method, experimented initially in Louisville, Kentucky, with concrete overlays of 90 mm and 50 mm, showed promising results in handling traffic loadings typical for low-volume roads, residential streets, and parking lots, while significantly reducing calculated stresses due to the bonding between concrete and asphalt layers. Notably, joint spacing was found to have a considerable effect on the rate of corner cracking, a prevalent form of distress.

Following the Louisville experiment, various UTW projects across the United States were documented, focusing on their construction specifics, mixture proportions, and observed pavement performance. Pavement condition surveys were conducted using the PAVER system protocol on selected projects, revealing that most sections maintained excellent to very good ratings, with an expected service life of eight to twelve years before the Pavement Condition Index (PCI) drops below 55 (Good).

This study underscores the importance of joint spacing and underlying asphalt thickness in influencing UTW performance. Future investigations should include detailed analyses of underlying asphalt conditions and other foundational properties to enhance the understanding and application of UTW for pavement rehabilitation. (Abstract generated by AI tool ChatGPT 4)