Hybrid fillers in carbon-fabric-reinforced cement-based composites

This paper presents the tensile behavior and the bonding between fabric and matrix of cement-based composites that had been reinforced with carbon fabric coated with hybrid fillers combining epoxy and active micro-silica particles (vs carbon fabric impregnated with epoxy or silica alone). The hybrid coating of the carbon fabric significantly improved the mechanical performance of the composites by virtue of a pozzolanic reaction at the fabric–matrix interface. The ways in which the hybrid fillers were mixed and applied to the fabric were found to impact the tensile behavior of the composites, namely, enhanced strength, ductility and toughness were obtained when the epoxy and silica particles were applied separately (giving epoxy inside the fabric bundles and silica at the bundle periphery), but greater stiffness was obtained when the epoxy and silica were first mixed together and then applied to the fabric (giving an epoxy–silica combination both inside and around the bundles).