Fuzzy logic model for investigating the effect of steel fibers on mechanical properties of concrete

This study aimed to use fuzzy logic model to predict various mechanical properties such as compressive strength, flexural strength and post-peak deformation of steel-fiber reinforced concrete. For this purpose, five different dosages of steel fibers (10 kg/m³, 12.5 kg/m³, 15 kg/m³, 17.5 kg/m³ and 20 kg/m³) were used in the mix design. A total of 3 specimens (cylinders and beams) were casted for each fiber dosage and experimentally tested. The experimental results were compared with the simulated results obtained from fuzzy model using fuzzy logic toolbox provided in MATLAB®. It was found that the addition of steel fibers improved the flexural strength and post-peak deformation capability of test specimens by almost 12% and 20% respectively. The compressive strength of specimens also increased by 9.15%, when the amount of steel fibers was increased from 10 to 20 kg/m³. Overall, the compressive strength reduced with the addition of fibers as compared to specimens with no fibers. Similarly, it was also observed that fuzzy model can predict the study parameters within acceptable accuracy and the percentage difference between the simulated and experimental values was below 7.5%.