Investigation on electromagnetic pulse shielding of conductive concrete

Abstract

Electromagnetic radiation is generated naturally or artificially by weapons capable of affecting the power grid and modern electronic devices; this poses a threat to a nation's defence, hospitals and communication systems. This study focused on designing and developing electromagnetic interference (EMI) shielding cement-based concrete using locally available materials. The shielding effectiveness (SE; in dB) of conductive concrete was assessed using a newly designed and fabricated metallic testing chamber with a monopole antenna (1.46 GHz) and a vector network analyser. A maximum SE of 36 dB was achieved experimentally in conductive concrete with magnetite and graphite aggregates and 2% steel fibres. The developed conductive concrete has a higher (around three times) SE than normal concrete with a similar range of compressive strength. A simulation study was carried out to predict the SE of the developed conductive concrete with the aid of CST Microwave Studio simulation software and validated with experimental results. The durability of the conductive concrete was assessed; it was observed to have low permeability and porosity. The research outcomes of this study form a stepping stone towards the design and development of conductive concrete against EMI.