Influence of coating and reinforcement volume fraction on woven basalt TRC: An experimental study

Textile Reinforced Cement (TRC) composites are widely investigated as a slender alternative to steel-reinforced concrete. Most existing studies focus on glass or carbon fibres as reinforcement. Literature on the flexural behaviour of basalt TRC, and more specifically on the coating of basalt fibres, remains sparse. The present study investigates the flexural behaviour of TRC reinforced by two-dimensional woven basalt textiles. The experimental program focuses on the impact of the reinforcement volume fraction and the coating. First, the mechanical behaviour of basalt fibres was characterised by tensile tests, while the bond with the mortar matrix was investigated by pullout tests. Next, four TRC configurations with varying reinforcement volume fraction and coating were tested under four-point bending. Epoxy impregnation increased the tensile strength of basalt yarns twofold and triggered pullout behaviour from the cement matrix. Using higher reinforcement volume fraction and coating in TRC significantly improved the flexural behaviour, i.e. more than doubled the post-cracking stiffness and the failure load. Also, the number of flexural cracks increased while their opening remained smaller (below 120 µm up to a displacement of 10 mm), as observed by Digital Image Correlation images of the flexural tests. Coated basalt reinforcements thus outperform in flexural applications.