كليدواژه :
gyration , tensile strength , Freeze-thaw durability , gyratory compactor , roller compacted concrete
چكيده لاتين :
Roller compacted concrete (RCC) is a durable, economical, low maintenance
material for low speed, heavy duty paving applications. However, it is difficult to
prepare laboratory specimens to represent field performance, because RCC is very
dry and requires considerable compactive effort to achieve field densities. The
gyratory compactor, commonly used to prepare hot mix asphalt specimens, may be
used in preparing specimens for laboratory testing. Materials and mix designs from
two industrial paving projects were used to prepare specimens for comparison.
Results indicated that the gyratory compactor produced specimens with mechanical
properties consistent with those achieved in the field. Specimens had high strength
and consistent density, with low variability. The effects of density and specimen size
on compressive and splitting tensile strength were investigated. The number of
gyrations applied to the specimen may be used to duplicate the desired field density.
Moreover, the effects of water-cement ratio and degree of compaction on the freezethaw
resistance of gyratory compacted RCC have been investigated. Due to the
consistency and compatibility of results obtained, the gyratory compactor may be
used to replace the modified Vebe apparatus, the vibrating table, and the vibrating
hammer because of some limitations in preparing RCC specimens using these
methods.