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Roller compacted concrete

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Roller compacted concrete is a dry concrete with no slump. Rollers are used to consolidate the roller compacted concrete. RCC has been used in dams and highways. This type of concrete has special properties. The mixture should be dry enough to support the mass of roller during the consolidation process. However, it should be wet enough to allow even distribution of cement during the mixing and consolidation process. In the event of placing RCC over a hardened concrete layer or at a cold joint. The segregation should be avoided, and a high plasticity mix layer should be placed at the start above the hardened concrete. The heat of hydration should be minimized for mass concrete by reducing the amount of cement used and the increase of aggregates size and amount without causing segregation of the mixture. Pozzolans can be used to improve the RCC properties. The replacement of  60-80% of cement content with PFA (pulverized fly ash) has proved a successful result for dams. 

 The high strength and toughness of roller-compacted concrete make it a good option for the construction of pavement. the using of RCC in construction pavement improve the pavement resistance to rutting, span soft localized subgrades, reduce pavement deformation under heavy, reduce the deterioration from spills of fuels and hydraulic fluids, reduce the pavement softening under high temperatures




Figure 1

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