Investigation on the tensile fracture energy of the steel fiber reinforced concrete (SFRC)

The use of steel fiber reinforced concrete (SFRC) benefits the concrete to have enhanced strength, toughness, and ductility. To correctly model the SFRC, the fracture energy and tensile strength are the key parameters. These parameters are usually governed by the volumetric fiber content of the steel fiber to the concrete volume. For that purpose, three concrete cylinders tested under compression and tensile splitting and three SFRC notched beams with different volumetric fiber content (Vf = 0.0%, 1.0%, 2.0%) are investigated. Dramix 4D 65/60 BG with hooked end type steel fiber is used. The length of the steel fiber is 60 mm, the aspect ratio is 65, and the diameter is 0.9 mm. The design concrete strength is 30 MPa. The concrete cylinder has a diameter of 100 mm and a height of 200 mm. The SFRC beam specimen dimension in mm is 200 (width) x 300 (height) x 600 (length). The beam notch height is 100 mm. The SFRC beam specimens are tested under the three-point bending test. The experimental investigation found out that the presence of the steel fiber significantly enhances both the concrete compressive and tensile strengths. The tensile fracture energy also increases significantly.