Comparison of Nuclear and Core Pavement Density Measurements

Abstract

Quality of highway construction is a major concern for highway agency engineers and contractors, and density of asphalt‐concrete pavement is one of the primary quality‐control parameters. The present study evaluates the use of the nuclear gauge as a prospective quality‐control tool by comparing nuclear‐gauge performance with core density measurements. Density measurements were recorded by the contractor and the highway department using both core and nuclear‐gauge methods on four paving projects, and statistical analyses conducted to compare the results. The analyses indicate that there is no statistical difference between the testers (contractor or highway department) or in the variability of the measurements obtained by the different methods. However, it is observed that the means of the measurements obtained by the different methods are statistically different and that density variability depends on type of mix. A multiple‐regression model is developed that correlates core density with nuclear gauge readings and type of pavement.