On the Electromagnetic Interference Shielding Effect of Cementitious Gypsum Tiles Containing Biochar

Abstract

With the rapid advancement of technology and progressive deployment of the 5G network in Singapore, electromagnetic interference due to the proliferation of devices that emit EM waves becomes a growing concern. As one of the most widely used materials in construction, it is desirable to enhance properties of cementitious materials to better shielding against EMI. This study investigates the electromagnetic shielding effect of cement mortar containing biochar with different amounts of water and the inclusion of gypsum to the matrix. Results obtained suggested no relationship between quantity of initial mixing water and total shielding effectiveness with the exception of the reflection component in the frequency range of 3.1 GHz - 3.57GHz which improved with higher water content. Water evaporation in samples was found to have no clear impact on EMI SE as samples containing biochar had experienced changes in both directions for maximum SE and bandwidth despite the continued decrease in mass throughout the 3 weeks. Whereas gypsum and plain mortar samples, despite showing no mass loss in week 3, experienced continued decrease in EMI SE. Experimental results also showed that addition of gypsum has led to lowered shielding effect as compared to plain mortar.