Influence of fiber treatment methods on the mechanical properties of high strength concrete reinforced with sisal fibers

The science of adding natural fibers to concrete results in an engineering material that is environmentally friendly and has the potential of promoting sustainable development in the construction industry. However, the challenge in adding natural fibers to concrete is that, they are hydrophilic in nature and this affects the bonding between the fibers and the concrete. To avert this problem three different fiber treatment methods namely, chemical, thermal and hybrid treatment methods were conducted on the sisal fibers to investigate the effect of the fiber treatment methods on the mechanical properties of sisal fiber reinforced concrete. The treated fibers were mixed with concrete with percentage fiber content of 0.5 %, 1.0 %, 1.5 % and 2 % and their compressive strength, tensile strength and flexural strength were tested. The experimental results showed that all the treatment methods considered led to an improvement in the tensile strength of the sisal fiber reinforced concrete. The compressive strength was also improved by the thermal and hybrid treatment methods, however, the chemical treatment method led to a reduction in the compressive strength. With regard to the flexural strength, all the treatment methods considered led to a reduction in the flexural strength when compared to the concrete without fibers. •Three different fiber treatment methods namely, chemical, thermal and hybrid treatments were considered under this study.•All the treatment methods considered led to an increase in the tensile strength of sisal fiber reinforced concrete.•The thermal and hybrid treatment methods improved the compressive strength of the sisal fiber reinforced concrete.•However, the chemical treatment method led to a reduction in the compressive strength of concrete.