Plasma-mediated nano-silica deposition to enhance thermomechanical robustness of carbon textile-reinforced concrete

Carbon textile-reinforced concrete (CTRC) lacks thermomechanical robustness at the textile/concrete interface. This study investigates atmospheric-pressure plasma (APP)-mediated nano-silica (NS) deposition as a promising strategy, evaluating its effects under thermal exposure up to 400 °C. While bulk material properties remained intact, the roving/matrix interfacial transition zone (ITZ) underwent notable physical, chemical, and structural transformations. A performance-driven index introduced herein to quantitatively assess thermomechanical robustness showed over a tenfold increase for NS-deposited rovings at 300 °C, contrasting with a severe drop below 0.2 for epoxy-coated counterparts. These results highlight the interplay between matrix-polymer interlocking and the chemical-structural evolution of the hydration products in the ITZ, with remarkable bond improvements attributed to the formation of a cohesive calcium silicate hydrate (C–S–H) network structure. Despite heating-induced progressive dehydration shrinkage and reduced interglobular cohesion, C–S–H particles remained tightly packed and interconnected in the ITZ, mitigating macrocrack propagation, enhancing frictional bonding, and preserving microstructural integrity. • Both pristine and epoxy-coated rovings undergo severe bond deterioration by heating. • The presence of CH and microcracks in ITZ compromises thermomechanical robustness. • NS deposition refines the ITZ, enabling high bond retention capacity after HT exposure. • Cohesive C-S-H network structure sustains bonding interaction despite collapse at HT. • Interplay between matrix-polymer interlocking and chemical-structural evolution in the ITZ.