Field Compaction Evaluation of NCAT Test Sections: A Case Study with the Density Profile System(DPS)

Abstract: In-place density is a fundamental site characteristic that directly influences the performance of asphalt pavements. Inadequate compaction combined with accelerated traffic effects can result in a pavement structure with decreased durability and stiffness, increased potential for fatigue cracking and rutting, and moisture susceptibility. It has been widely adopted that for every 1% increase in air voids or percentage reduction in compaction, the pavement service life is reduced by about 10%.

A field study was conducted to evaluate the impact of in-place compaction on the performance of asphalt pavement sections built at the National Center for Asphalt Technology (NCAT) Test Track that were subjected to 10 million equivalent single axle loads (ESALs). In-place density was collected using the Density Profile System (DPS). Specifically, density measurements taken right after construction and at the end of the research cycle (post 10 million ESALs) in two locations: in-between wheelpaths and wheelpaths. Additionally, field performance was characterized through several surface indicators such as rutting, cracking, and roughness.

Statistical analyses were conducted to determine density differences between wheelpath and in-between wheelpaths locations among the different sections evaluated. Main findings revealed higher compaction levels after 10 million ESAL’S for wheelpath locations when compared to locations in-between. Additionally, sections that have experienced higher deterioration rates are related with lower compaction levels from construction. This can be interpreted as reductions in compaction can lead to reduction in pavement service life indicated by surface performance parameters

Keywords: Asphalt Pavements, Density, Density Profile System, Compaction.