Preliminary Investigation of the Feasibility of Using a Superpave Gyratory Compactor to Design Cement-Treated Aggregate Mixture

Abstract

Cement-treated aggregate mixture (CTAM) is widely used in many countries. To design this mixture using the vibration compaction method brings about many problems, such as serious inconsistencies in key parameters and strong vibration energy and noise imposed on adjacent buildings and people. This work presents a preliminary investigation of the use of Superpave gyratory compactor, which has been widely used to compact hot mix asphalt in the laboratory, to design CTAM. The 3-2-2 mode of the locking point was used to determine that the gyration compaction number Ndesign should be 105. The performances of the CTAM specimens prepared using gyration compaction were compared with those prepared using the Proctor and vibration compaction methods. Compared with Proctor and vibration compaction, gyration compaction had a smaller influence on aggregate degradation. Also, the optimal moisture content after gyration compaction was the minimum. The index values for maximum dry density, unconfined compressive strength and dry/temperature shrinkage coefficient after gyration compaction were between those for Proctor compaction and vibration compaction. It can be concluded that it is feasible to design CTAM by using a Superpave gyratory compactor to compact the mixture for 105 cycles.

Keywords

• cement-treated aggregate mixture
• Superpave gyratory compactor
• compaction level
• locking point