Physical and mechanical properties of light and heavyweight concretes reinforced with basalt fibre

The purpose of this study was to investigate the effect of basalt fibres in concrete mixtures to improve their physical and mechanical properties. The study used Portland cement grade PC400 D0, granite crushed stone, perlite gravel fill, and sand coarse aggregate to create concrete mixtures of various densities. The findings of this study confirmed that the optimum dosage of basalt fibres plays a key role in achieving the best mechanical properties of concrete. Upon proper dosage of up to 3%, the fibres improve the structure of concrete, increasing its strength and crack resistance. However, when this level is exceeded up to 5%, agglomeration of fibres and lack of cement paste to bind the aggregates result in lower flexural strength of concrete. The study also revealed that the tensile strength and compressive strength of concrete varies with basalt fibre content. The tensile (flexural) strength showed an increasing trend with the addition of up to 3% fibres, with a maximum increase of 11.3% over the original sample. However,when the basalt fibre content was further increased, the strength started to decrease, emphasising the significance of maintaining the optimum dosage. Concrete shrinkage also varied with fibre content: as the basalt fibre content increased, shrinkage decreased due to the formation of an internal reinforcing structure that prevents the movement of concrete particles. In case of lightweight concrete, analogous trends were discovered: compressive strength and flexural strength increased up to a certain level of basalt fibre content, but then decreased when the optimum dosage was exceeded. The findings emphasise the significance of careful control of basalt fibre dosage in the design of concrete structures, as insufficient or excessive basalt fibre content can adversely affect the mechanical properties of concrete. Optimised use of basalt fibres can considerably improve the strength, crack resistance, and other characteristics of concrete, making it more stable and durable under various service conditions