The presence of chloride ions in steel-reinforced structures leads to the corrosion of the reinforcement thus compromising the integrity and strength of the structure. Thus, it is of great importance to be able to non-destructively detect and evaluate the free chloride content in concrete. To that end, an investigation was initiated where two mortar cubes were soaked in distilled water and saltwater solutions, respectively. Their temporal microwave reflection properties were measured using open-ended rectangular waveguides on a daily basis for three cycles, each lasting 35 days. A semi-empirical electromagnetic model was then developed to simulate the reflection properties of the cubes. The outcome of the model describes the water and saltwater distribution within the cubes. In addition, the distribution curves also depict the manner in which the water and saltwater contents vary within the cubes from day to day. This paper presents a comparison between the water and saltwater distributions obtained from this model. The results of such a comparison would then indicate the mechanism of mass transport within the cubes
