Analysis of water and salt movement within mortar assuming a capillary flow

In order to understand basic characteristics of salt movement within concrete under a salty environment, one-dimensional water and salt movement within mortar was initially investigated by experimental and numerical analysis. For the numerical analysis, it was assumed that water is driven by both capillary flow and vapor diffusion, while the movement of salt is governed mainly by capillary flow. To evaluate the assumption and the analytical procedure, four different water-cement ratios of mortar were investigated. The water contents in mortar were calculated by mass difference of sliced mortar pieces before and after oven drying. The amounts of salt were estimated by the potentiometric titration method after crushing mortar pieces under 140 μm. A good agreement in experiment and numerical analysis for both profiles of water and salt contents was found. Therefore, the present procedure enables to represent water and salt movement in mortar.