Ultrahigh-Pressure Watercutting Treatment of Flushed Chip Seals in the United States

Abstract

This paper discusses the effectiveness and durability of ultrahigh-pressure (UHP) watercutting as a preventive or corrective maintenance strategy to treat flushed chip seals in the United States. The data presented here originated from an implementation project conducted in 2011–2012 in which UHP watercutting was used to treat chip-seal-surfaced roads at 13 field sites located in four FHWA climatic regions in Texas. Initial treatment effectiveness varied depending on the site but typically was high, with an average increase in pavement texture of about 200% and an average increase in friction of about 135%. Therefore, the UHP water-cutting treatment did improve pavement texture and friction. Follow-on monitoring of the field test sites over an 18-month period showed that the surface friction and texture values achieved at treatment survived at or above the desirable performance threshold for seven of 13 sites, and these values survived at or above the maintenance threshold for 12 of 13 sites. The life expectancy achieved by UHP watercutting varied in terms of pavement texture and friction values. Predictive decay models indicated that texture and friction values would last 1 or more years at 90% of the test sites. For 40% of the test sites, the treatment would last four or more years, and these life expectancy estimates were consistent with published data. Overall, the results from this study were promising for the application of UHP watercutting to chip seal maintenance in the United States.