This paper presents an experimental study of combined use of steel fibers and stirrups as shear reinforcement in reinforced concrete beams as a more practical solution than using any one of them alone. For this purpose twelve T-shaped beams were tested. The studied variables were; volume percentage of fibers and transverse reinforcement ratio. To give an economical design, only low percentages of stirrups were used in the test beams.The test results showed that steel fibers are more efficient in increasing ultimate shear strength and ductility when used with small amounts of stirrups, and this efficiency will decrease when using large amounts of stirrups . The tests also demonstrated that the contributions of steel fibers and stirrups are not cumulative and there are limits for an optimum combination between them, which lead to higher shear strength and ductility. A pre-existing equation for estimating shear strength for steel fiber reinforced concrete beams without stirrups was further extended to include the effect of stirrups in low ratios.
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