Influences of fiber content on properties of self-compacting steel fiber reinforced concrete

This paper deals with the mix design and mechanical properties of self-compacting steel fiber reinforced concrete (SFRC). By using superplasticizers and mineral admixtures such as slag and fly ash, three SFRC of different fiber contents (0.5, 1.0 and 1.5%) and one plain concrete with high fluidity (slump approximate to250mm) have successfully been developed without bleeding or segregation. The compressive and flexural strengths, flexural toughness as well as shrinkage and creep of the four mixes of concrete were studied. It has been shown that increasing steel fiber content can improve the flexural strength and toughness of self-compacting SFRC even though its compressive strength could be reduced due to the increase of air content. It has also been found that the addition of steel fibers can efficiently reduce both the autogenous and drying shrinkages of the self-compacting SFRC. The models of ACI Committee 209 accurately predicted the autogenous shrinkage of the plain self-compacting concrete but they overestimated its drying shrinkage and creep.