Effect of Density on Mechanical Properties and Durability of Roller Compacted Concrete and Mix Proportions of RCC Pavements in Cold Regions

Roller compacted concrete (RCC) is a durable, economical, low maintenance material for low speed, heavy duty paving applications. However, it is difficult toprepare laboratory specimens to represent field performance, because RCC is very dry and requires considerable compactive effort to achieve field densities. Thegyratory compactor, commonly used to prepare hot mix asphalt specimens, may be used in preparing specimens for laboratory testing. Materials and mix designs fromtwo 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.

Keywords:

gyration , tensile strength. Freeze-thaw durability , gyratory compactor , roller compacted concrete