Effect of nanosilica addition on the mechanical properties of cement mortars with basalt fibers with or without silica fume

Fiber reinforced concrete is widely used throughout the world however to reveal its full potential, optimization with different additives should be asserted. In this study, effect of the three different parameters were diagnosed by means of compressive strength, flexural strength and fracture. Ordinary Portland cement mortars were studied with three different basalt fiber contents (0, 0.5, 1%), three different nanosilica addition (0, 1, 2% by wt. of cement) and also silica fume incorporation (0, 5% by wt. of cement). The results showed that adding basalt fiber significantly improved the flexural strength and toughness properties and also with the addition of nanosilica the increase in flexural strength boosted up to 23% level of increase at the presence of silica fume. This synergy effect was found to be significant when incorporating basalt fibers. When nonfibrous specimens were inspected, it is seen that addition of nanosilica was not significantly efficient increasing neither the flexural strength nor fracture properties.