Influence of W/C and Moisture Content on Capillary Adsorption of Concrete

In practice, almost all of the concrete structure exposed to environment are partial saturated except the concrete structure under water. So, the influence of W/C and moisture content on capillary absorption of concrete was investigated. Results indicated that the ultimate saturation increases with W/C linearly. The porosity and pore size distribution of concrete will be changed with W/C. Concrete with lower W/C with the same saturation absorbs less water and the rate of capillary absorption is also lower. The degree of saturation of the concrete plays a strong role on capillary adsorption. Concrete with lower saturation with the same W/C absorbs more water and the rate of capillary absorption is also quicker. The bigger of W/C, the bigger of the initial coefficient of capillary absorption and the bigger of saturation, the smaller of the initial coefficient of capillary absorption. The initial coefficient of capillary absorption increases with W/C linearly, while it decreases with saturation linearly within the accuracy of the measurements.