Influence of Different Lengths and Volumes of Basalt Fibre on Mechanical Properties of Concrete

Abstract

In this research work, the influence of basalt fiber lengths and volumes on mechanical properties of concrete such as compressive strength, flexure strength and split tensile strength are studied. 12 and 24 mm lengths of basalt fiber having the same diameter (13 µm) were used in the experimental work. The influence of 0.10%, 0.15%, 0.20%, 0.25%, 0.30%, 0.35%, 0.4% and 0.5% volume of basalt fiber on mechanical properties of concrete have been studied. The results of conventional concrete and basalt fiber reinforced concrete were compared. Normal strength concrete M30 grade was considered in the work and the mechanical properties were measured at 3, 7 and 28 days of hydration period. The experimental investigation shows that high dosage of fibers creates workability problems such as mixing, clumping and balling effects. Experimental results show that there is no improvement in the compressive strength of concrete when basalt fibers were added in plain concrete mix at all ages of concrete. Moreover, the compressive strength values become unstable when basalt fibers are added to concrete. Maximum value of split tensile strength and flexure strength was obtained for 0.35% (9.275 kg/m³) basalt fiber content for both 12mm and 24mm length of basalt fiber at all ages of concrete. Comparing both 12mm and 24mm basalt fiber lengths, the 24 mm length of fiber has shown superior performance in relation to flexure strength and split tensile strength. Overall, the optimum length of basalt fiber is 24 mm and the optimum volume fraction of basalt fiber is 0.35%.