Microwave Dielectric Properties Measurements of Sodium and Potassium Water Glasses


Dielectric properties of alkali silicates ((Na,K)2(SiO2)nO) or 'water glasses' are a critical input into the electromagnetic modeling of these materials, which have a broad range of applications. Recent increased interest in understanding geopolymerization of aluminosilicates with water glasses and the potential to improve understanding of the role of moisture in damage due to alkali-silica reaction (ASR) in concrete (where water glass is a suitable analogue for ASR gel) motivates this research. This investigation presents the results of microwave dielectric property measurement of twelve laboratory-produced (synthetic) water glass samples at X-band (8.2-12.4 GHz). Results show an exponential decay of loss factor as a function of increasing silica-to-alkali ratio, suggesting a correlation with increase in bound water in the samples and a decrease in the fluid ionic concentration. The results provide an insight into the temporal changes of the dielectric properties of ASR-affected materials, as well as geopolymers.


Electrical and Computer Engineering

Keywords and Phrases

Characterization; Computational Electromagnetics; Dielectric Materials; Geopolymers; Glass; Inorganic Polymers; Silica; Silicates; Sodium; Alkali-Silica Reaction; Cement Based Material; Dielectric Mixing Model; Electromagnetic Modeling; Exponential Decays; Ionic Concentrations; Microwave Dielectric Properties; Microwave Materials; Dielectric Properties; Alkali-Silica Reaction (ASR) Gel; Cement-Based Materials; Microwave Materials Characterization

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Article - Journal

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© 2016 Elsevier, All rights reserved.

Publication Date

01 Apr 2016