Strength, pore and corrosion characteristics of ceramic insulator powder-silica fume based ternary blended mortar

Abstract

This study investigates the compressive strength, porosity, water absorption, chloride penetration, and corrosion resistance of mortar in a ternary blended cementitious system that substitutes Portland Cement Type 1 (PCT) with varying proportions (15%, 20%, 25%, 30%, and 40%) of finely ground ceramic electrical insulator (CE) and silica fume (SF). To enhance the workability of the mortar, a superplasticizer (SP) was used, maintaining a consistent water-to-binder ratio (W/B) of 0.50. SEM-EDS microstructural analysis revealed a homogeneous composition with a high content of calcium silicate hydrate (C-S-H) gel, particularly notable in samples combining CE and SF. The incorporation of 5% to 20% by weight of CE and SF into the cementitious materials resulted in mortars that exhibited superior compressive strength compared to both the control sample and those containing only 10% SF. The use of very fine CE and SF also improved the mortars’ properties in terms of water absorption and chloride penetration. Furthermore, the addition of CE and SF significantly enhanced the mortar’s porosity and increased its corrosion resistance. These findings demonstrate the viability of ground ceramic electrical insulators as a cementitious material and emphasize the environmental benefits of reducing waste and alleviating disposal burdens by repurposing industrial by-products.