Innovative humidity measurement method for high moisture content of building materials

A wide range of measurement methods is available for determining material moisture. In the talk, the methods are briefly classified and their advantages and disadvantages compared. On the back of these considerations, the idea of an innovative moisture measurement process is presented. The measurement method is based on the microwave resonator process. This reacts very sensitively to moisture changes and in principle offers the possibility of very accurate measurements. The process uses the frequency dependence of the dielectric material properties. With the evaluation of the two resonances in different frequency ranges, a multiparameter system is present. Thanks to the specially dimensioned resonators, the measurement process is suitable for a very large moisture range: Both relatively low moistures of the brick body and high moisture contents of the starting products  can be measured. For the users in brick production, with the application of this measurement process, the crucial advantage is that the moisture readings can be used in real time for control in the production process. Long waiting times are eliminated, resources are saved.

Dr. Ralf Wagner, MFPA Weimar


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