Complex permittivity measurements for moisture and salinity characterization of building materials

In this paper, preliminary results of complex permittivity measurements of clay-brick material will be presented. The general aim of the experimental project is to correlate the measured permittivity of construction materials with the content of water and salt, in order to obtain information on the condition of ancient walls by using non-invasive techniques. The complex permittivity values reported in this paper have been obtained by waveguide measurements on samples of clay-brick dried and then immersed in demineralized water or in a saturated solution of demineralized water and NaCl.