Effect of origin, granulometric characteristics of binary fillers, and chemical modifiers on the structure and durability of fine-grained basalt fiber-reinforced concrete

This paper presents the results of an experimental investigation into the influence of the origin and particle size distribution of binary mineral fillers, combined with a polycarboxylate superplasticizer, on the structure and properties of fine-grained basalt fiber-reinforced concrete. It was established that a composition based on silica fume (10%) and a carbonate component (15%) provides a synergistic effect, resulting in the densification of the cement stone and improved mechanical performance. The results demonstrate that reducing the water-to-cement (W/C) ratio to 0.27 through the use of a superplasticizer (≈ 0.8%) promotes the formation of a dense microstructure and increases the compressive strength to 84 MPa. The addition of basalt fibers (4%) enhances crack resistance and the modulus of elasticity through three-dimensional spatial reinforcement. Furthermore, a reduction in porosity of over 20% was observed, alongside improved durability characteristics, including water absorption down to 2.6%, water impermeability up to W14, and frost resistance up to F600. Additionally, partial cement replacement ensures a reduction in CO 2 emissions to 340 kg/m 3 (over 40%), confirming the environmental efficiency of the developed compositions.