Study on strength parameters of steel fiber reinforced high strength concrete

Abstract

In general concrete is a brittle material having low tensile strength and is prone to cracking. The increase in compressive strength of High Strength Concrete (HSC) not only increases brittleness but also reduces the ductility of the concrete. The introduction of steel or polymeric fibers in HSC improves the ductility. In this context, the paper presents the results of the experimental study on the strength parameters of Steel Fiber Reinforced HSC such as compressive strength, split tensile strength and flexural strength. The HSC used M60 grade with steel fibers added by volume in the range of 0 to 2.5% with an increment of 0.25%. The length of fibers was 25 mm to 80 mm. The experimental results were used to develop Artificial Neural Network (ANN) model for the prediction of strength parameters. It was observed that the ANN model with 2-16-3 architecture trained with Levenberg-Marquardt rule resulted into satisfactory performance for the prediction of strength parameters. Further regression models were also developed based on the experimental data. It was found that all the three strength parameters increase with an increase in percentage of steel fibers. However, the compressive strength increases with increase in fiber length from 25 mm to 50 mm and then decreases when the fiber length becomes 80 mm, while the split tensile strength increases with increase fiber length. On the other hand, flexural strength shows mixed trend.