Non-destructive moisture measurement systems work from the surface to determine moisture content. As a result, the water content of near-sensor layers has the strongest influence on the delivered measured value. Accordingly, it is difficult to determine the moisture content in the inner core of a drying brick. By means of an ultrawide band microwave radar system (UWB radar), it is possible to observe the drying process of green bricks. Based on a comparison with a simulation of the drying process in the Delphin programme and implementation of the measurement results in the ZiTro programme developed specifically for the brick and tile industry, the spatial moisture distribution in green bricks at different times can be determined. For the measurement and the simulation, the climate data and the corresponding material properties are needed.
In the talk, the measurement system and measurements under laboratory conditions are presented. Possibilities for determination of the core moisture by means of the application-oriented dielectric moisture measurement system and the limitations derived from the results obtained are discussed.
Dr. Ralf Wagner, Material Research and Testing Institute at Bauhaus University of Weimar; Dr. Anne Tretau, Institut für Ziegelforschung Essen e.V.