Evaluation of Roller-Compacted Concrete Field Constructability with Mixture Volumetrics

Broadening the use of roller-compacted concrete (RCC) requires a better connection between field constructability and theoretical mixture volumetrics. Four RCC paving projects were visited in the central and southeast United-States to observe, test and document the construction process from the material constituents, proportions, mixing, paving, compaction, and surface finishing. Fresh RCC was sampled to determine variability of the mixture moisture content and proportions by wet sieving. Constituent materials were sampled at the plant for re-mixing in the laboratory where constructability was evaluated with the gyratory compaction and green property testing. Field density and DCP measurements were performed before and after roller compaction of each lift at both the edges and center of the lane. Hardened samples obtained near the test locations were analyzed for density and strength. Laboratory tests characterized the theoretical mixture volumetrics such as the intergranular voids (IGV) and ratio of voids filled by paste (VFP). Results showed agreement between in-situ and laboratory constructability through the volumetric compactive energy and green properties. RCC constructability was found to be highly moisture sensitive but was minimized by adequate and continuous moisture management in the field.