Effectiveness of vacuum saturation preconditioning regime for assessing water permeability of high performance concrete

Saturating high performance concrete (HPC) for assessing water permeability is a challenge. This paper reports a testing program established to determine the reliability and efficiency of an in situ preconditioning regime, the vacuum saturation, for the water permeability test. The vacuum saturation regime was examined through changing the parameters used and to justify if the field conditioning regime is able to yield similar results as in the laboratory, the results after vacuum saturation were statistically analysed and compared with that after incremental immersion. Its accuracy was further examined by additional experiments, whereas factors considered include different concrete mixes and different initial moisture conditions. The results suggest that the proposed method can eliminate the influence of moisture for different HPCs under the high initial moisture content. It is not effective, when the initial moisture content is low.