Effect of different fiber reinforcements on the electromagnetic performance and mechanical properties of zeolitic tuff/ calcite-based geopolymer composites

Exposure to electromagnetic (EM) radiation is known to cause various adverse effects, including malfunctions in electronic equipment and health problems in humans. Consequently, researchers are endeavoring to mitigate this risk by employing construction materials to attenuate EM radiation. This study focuses on improving EM shielding effectiveness by using innovative construction materials. Specifically, attention is given to zeolitic tuff/calcite-based geopolymer composites (GC) reinforced with four types of fibers: polypropylene, brass-coated micro steel, basalt and carbon at 1 %, 2 %, and 3 % percentages. The study evaluates the effects of these fibers on the workability, water absorption, and shrinkage, compressive and flexural strengths properties of the reinforced GCs, as well as its electromagnetic shielding performance between 900 and 6000 MHz frequencies. The 3 % carbon fibre-reinforced GC tiles have been shown to provide the highest shielding effectiveness of all the materials tested, with a shielding value of 56.6 dB at 5500 MHz. In addition to this, they have also been found to have satisfactory mechanical properties, with a minimum length change. This performance is adequate to block Wi-Fi signals within this frequency range and is critical for shielding against computer and television radiation. The greatest compressive and flexural strengths at 90 days were achieved on the GCs reinforced with 1 % carbon fiber.