Capillary Transport in RCC: Water-to-Cement Ratio, Strength, and Freeze-Thaw Resistance

Water transport plays a critical role in the freeze-thaw (F-T) response of concrete. This work aims at appreciating various water transport parameters in roller-compacted concrete (RCC) for different pavement applications and correlating these with its F-T performance. The test variables include cement content (100 to 450 kg/m3), water-to-cement ratio (w/c) (0.27–1.27), surface finish, and age of concrete. Measurements of concrete mixtures include sorptivity (S), desorptivity (R), surface inflow velocity (u0), compressive strength, and F-T resistance. Indexes, including inflow velocity, are used to evaluate transport properties of different mixtures. Interaction diagrams are developed to characterize the relationships among sorptivity, desorptivity, w/c, compressive strength, and F-T durability. The results indicate that sorptivity of RCC is comparable to that of conventional concrete and that desorption behavior is linearly related to sorptivity. Surface finish has a definite impact on sorptivity, but its effect on desorptivity is negligible. Curing age refines concrete pore structure, increasing resistance to water ingress. These results provide a better understanding of transport properties of RCC and its influence on F-T resistance.