National Highways Designated Funding Trial – Continuous Compaction Control

HDS took part in a National Highways sponsored designated funding project to establish a basis for the use of continuous compaction control technology on highways earthworks construction. The rationale behind the project was to find ways to reduce the requirement for manual in-situ testing of density and stiffness, as well as to find a better way to prove compliance with method compaction requirements.

HDS established used continuous compaction control (CCC) systems, consisting of high-accuracy GPS and accelerometers mounted to two rollers to monitor roller passes and material stiffness. Using an existing standard (CEN-TS 17006:2016), HDS established a trial methodology.

The trial was limited in terms of materials assessed but good correlation results were found to exist between roller-measured stiffness and in-situ tests measured by nuclear density gauge, lightweight deflectometer (LWD) and plate-measured California bearing ratio (CBR). Roller passes were accurately measured, ensuring roller drivers were able to hit their targets for 100% of the area under compaction.