Plain Cement Concrete (PCC) is not used as structural concrete hence it has lower strength (max 3000 psi) requirement than Reinforced Cement Concrete (RCC) which is used as structural concrete (strengths ranging from 3000 psi to 15,000 psi for high strength concrete).
In light of the above, RCC has a very different mix design as compared to PCC. However, for a strength of around 3000 psi they will both have similar mix design. For higher strengths, RCC mix design incorporates admixtures, supplementary cementatious material and different gradation of aggregates than PCC.
PCC is generally used as footing bed, platforms and for roads where it has to take compression force only.RCC is used in building frame or structural elements of the building where it has to take both compression and tension also.