Evaluation of Moisture Content in Concrete with Microwave
Generally, any chemical or physical change in a material may cause variation in its permittivity and permeability. The propagation of microwave through the material can be affected by these variation in properties. The analysis of microwave propagation through materials may therefore provide a means for condition monitoring. This paper utilizes a one-dimensional scenario, demonstrating the feasibility to link measurable reflection and transmission coefficients of microwave to concrete permittivity and permeability, which are essentially associated with water content in concrete. As a result, water content can then be monitored through the measurement of these coefficients. The study also demonstrates the feasibility of using the same technique to estimate the thickness of the concrete that microwave propagates through.
Hong-Yuan Liu, Xiaozhi Hu and Mark Hoffman
X. M. Wang et al., "Evaluation of Moisture Content in Concrete with Microwave", Key Engineering Materials, Vol. 312, pp. 311-318, 2006