Superpave Gyratory Compactor as an Alternative Design Method for Roller Compacted Concrete in the Laboratory

Abstract

The introduction of the Superpave gyratory compactor (SGC) to pavement laboratories was a large step for the design process of hot mix asphalt (HMA). Considering the similarities between HMA and roller compacted concrete (RCC), the use of SGC in the design work of RCC pavement can offer many advantages. This study covers a wide range of RCC mixtures that can help to set the limits of using SGC for RCC mixture design. Therefore, a detailed experimental matrix was developed by taking various mixture parameters and gyration levels into account. Moreover, four different RCC mixtures determined on the basis of optimum mix designs were also produced by vibratory hand roller in order to simulate the field compaction conditions in the laboratory. The SGC results showed that for the same gyration level, the compaction ratio changes when the mixture is changed. The results also concluded that the gyration level for the same mixtures was the least significant factor affecting the mechanical performance. Hence, SGC is more effective in predicting the behavior of the fresh RCC. On the other hand, the mixtures with similar compaction ratios compacted by SGC and hand roller resulted in a similar strength level. Therefore, for RCC specimens produced by the SGC method, targeting the sample density (i.e., compaction ratio) is recommended due to its ease of applicability under field conditions rather than making a design based on the number of gyrations as used in conventional SGC applications.