A graphic based approach for the mix design of steel fiber reinforced concrete

Steel Fiber Reinforced Concrete (SFRC) is a special type of concrete of which brittleness problem is eliminated. Day by day, the use of this concrete type is growing up. With the wide using of SFRC, some requirements have emerged. One of these requirements is a practical mixture design of SFRC for both academic researches and applications. In this study, it is aimed to eliminate this need with a graphical design approach for SFRC. with this aim, SFRC mixtures which had different aggregate gradations, different cement dosages and water/cement ratios, different fiber fractions and types were produced. Fresh concrete properties were determined using Slump and Ve-Be tests. And then, compressive strength and splitting tensile strength tests were performed with 150 mm sized cube specimens. Flexural strength and the toughness values of SFRC specimens were determined using 150/150/500 mm and 80/80/300 mm sized beam specimens. Compared to all experimental results, the relations between concrete mix composition, workability and strength were revealed with the graphics and convenient graphics were brought together to create a monogram. Using this monogram, it was tried to bring a new perspective to SFRC design. In addition, Ultrasonic Pulse Velocity measurements of hardened concrete specimens were performed, and an important contribute were made for determining the strength properties of SFRC by using a non-destructive method at the end of the tests. It is another important parameter that toughness is a superior property of SFRC compared to the normal concrete. Toughness properties of SFRC specimens which had different compressive strengths were also investigated in this study. As conclusion, graphics which can help to anticipate accurately and practically strength and toughness properties of SFRC mixtures with different design inputs were revealed. Through these graphics, in research and application fields, it can be possible to minimize loss of material and time during trial studies. Thus, the goals of the studies can be achieved more economically and practically.