Determination of capillary conductivity data from steady state flow experiments

The measurement of moisture transport properties requires the knowledge of both, the flow rate and the induced moisture potential gradient during the corresponding experiment. Within the hygroscopic moisture content range, cup measurements are a common practise to determine the vapour diffusivity under steady state flow conditions in such a way. For the higher water contents, however, a comparable measurement technique is not commonly applied, yet. The paper presents a new experimental device enabling the measurement of the liquid water conductivity at high degrees of saturation. The measurement principle is explained and the developed experimental set-up is shown. Moreover, measured moisture conductivity data of a large extent of building materials is presented and discussed on the basis of a statistical sensitivity analysis.