Comparison of water and saltwater movement in mortar based on a semiempirical electromagnetic model

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 interest to nondestructively detect and evaluate free chloride content in concrete. To this 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. Subsequently, a semiempirical electromagnetic model was 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, these distributions depict the manner by which the water and saltwater content temporally vary within the cubes. The presence of salt causes the saltwater distribution to be different than the water distribution in the respective cubes. 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 influence of salt on the mechanism of mass transport within the saltwater cube.