Evaluation on compactibility and workability of roller-compacted concrete for pavement

ABSTRACT

The use of roller-compacted concrete pavement or RCCP has increased steadily in the past few decades. It is an economical version of conventional concrete pavement; whereas the construction cost of other types of pavement is constantly rising. In its mixture design, compactibility is an important factor for achieving high strength while workability is an essential factor for providing workable material. However, the satisfaction of both properties is difficult to achieve because of the effect of various factors such as aggregate gradation and water content. Appropriate combination of materials is significant for providing adequate compactibility and workability of this concrete. In this study, twenty-one mixtures of roller-compacted concrete (RCC) with six different water contents for each of four aggregate gradations were evaluated using Modified Proctor and Vebe tests. Dry density was used to characterise compactibility of RCC while Vebe time was used to express its workability. It was found that Vebe time increased as sand/aggregate, or s/a, ratio increased and decreased when water content rose. On the other hand, maximum dry density decreased as s/a increased. The well-graded aggregates, 58 and 50% of s/a, were found to give its maximum dry density with satisfactory workability. Interestingly, it was learned that the range of appropriate water content corresponding to acceptable workability is narrower than that of appropriate water content corresponding to the acceptable dry density which indicated that it is more crucial and difficult to get appropriate workability than acceptable dry density.

KEYWORDS:

• Roller-compacted concrete
• workability
• compactibility
• Vebe time and maximum dry density

Acknowledgement

This study was conducted under research project (Development of Eco-Friendly Pavements to Minimize Greenhouse Gas Emissions) funded by the Ministry of Land, Infrastructure and Transport (MOLIT) and the Korea Agency for Infrastructure Technology Advancement (KAIA). The authors would like to thank the members of research team, MOLIT and KAIA for their guidance and supports throughout the project (No. 15LRPB07926102).

Additional information

Funding

This research was supported by the Ministry of Education (MOE); National Research Foundation of Korea (NRF) through the Human Resource Training Project for Regional Innovation [grant number 2014H1C1A106708]; Ministry of Land, Infrastructure and Transport (MOLIT) and the Korea Agency for Infrastructure Technology Advancement (KAIA) [number 15LRPB07926102].