Effect of steel fibers on the mechanical properties of natural lightweight aggregate concrete

In this study, the effect of steel fibers on the mechanical properties of pumice aggregate concrete was investigated. In order to determine the effect of steel fiber ratio on the mechanical properties of concrete, (1) 25%, 50%, 75%, and 100% pumice ratios were used instead of natural aggregate by volume, (2) 0.5%, 1.0%, and 1.5% steel fiber ratios were used by volume of the sample and (3) also, 300 kg/m3 cement dosage and 3 ± 0.5 cm slump were used. The test results showed that the increasing pumice aggregate ratio decreased the unit weight and the mechanical properties of the concretes. When compared to the control sample that contains no fiber, with the increase of steel fiber ratio in the mixtures unit weight, compressive strength, splitting-tensile strength and flexural strength of concretes increased up to 8.5%, 21.1%, 61.2% and 120.2%, respectively. Moduli of elasticity and deformation capability were decreased with increase of pumice aggregate and steel fiber ratio in the mixture.