Prediction of mechanical properties of high strength steel fibre reinforced concrete using linear regression techniques

In this study, researchers investigated the mechanical properties of high-strength steel fiber-reinforced concrete (HSFRC). The experimental study involved evaluating high strength concrete (HSC) using various steel fibre contents (ranging from 0.25% to 2.00%) and different water-cement ratios (WCR) (0.25, 0.30, 0.35, and 0.40). Adding 1.50% steel fibre to HSC led to an increase in compressive strength (CS). Specifically, the CS improved by 13.42% to 15.19% for WCR of 0.25, 0.30, 0.35, and 0.40. Including 1.50% steel fibre enhances split tensile strength (STS). The STS increased by 25.89% to 32.62% for the same WCR. High-strength concrete with 1.50% steel fiber exhibited improved flexural strength (FS). The FS rose 29.00% to 35.07% for the specified water-cement ratios. The study also considered the modulus of elasticity (ME) at 28 days. Interestingly, the strength of HSC decreased as the WCR increased. Lower WCR generally contributed to better mechanical properties. The experimental results were compared with linear regression analysis and existing empirical formulas. The regression analysis demonstrated good agreement with the experimental findings. Overall, the optimal steel fibre content was 1.50% across all WCR, significantly improving mechanical properties. The study provides valuable insights for designing HSC with enhanced performance.