A basic and necessary ingredient for simulating the fracture process in quasi-brittle materials is the fracture energy, G_F. The most commonly used way of measuring the G_F in these materials, is the method proposed by RILEM TC-50. Although this procedure is widely examined for plain concrete, its applicability to steel fiber reinforced concrete (SFRC) needs further evaluations. In this paper, in addition to the RILEM procedure, two new approaches are applied to the results of the three point bend tests to measure the G_F of plain concrete and two types of SFRC. Notched beams with three different notch depths are used to determine the G_F. The two new approaches seem to have less reliance on the tail of the load-displacement curves. These new methods are particularly more suitable for composite materials such as SFRC, which exhibit a long tail in their load-displacement response. The results of the three procedures were comparable to each other. In addition, the effect of the volumetric fraction of fibers on the GF in SFRC for two low percent volumetric content of steel fibers, 1% and 1.5%, is examined.
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