Flexural tensile behavior of steel fiber reinforced concrete beams: Experiment and numerical model

Abstract

The experimental and numerical modeling of steel fiber-reinforced concrete (SFRC) beams subjected to three-point bending according to EN 14651:2005 are presented in this paper. Smooth round copper-coated steel fibers (HF5913) with varying volume fractions (0%; 0,5%; 1% and 1,5%) were used in concrete beams with a compressive strength 60 MPa. The test specimens had dimensions of 150x150x550 mm. Experimental results showed that the flexural tensile strength of conventional concrete beams was approximately one-twelfth of their compressive strength. In contrast, steel fiber-reinforced concrete  beams exhibited significantly higher flexural tensile capacity, reaching between one-ninth and one-sixth of the compressive strength, depending on the fiber content. These findings indicate that the incorporation of steel fibers into concrete considerably enhances its flexural tensile performance. The good agreement between the experimental results and the numerical simulations of the mechanical behavior of SFRC materials — based on the phase field method recently developed by our team — demonstrates the model's accuracy. Through this model, the flexural tensile behavior of SFRC was further analyzed and discussed.