A computational analysis is presented to predict the ultimate and cracking shear strength of steel fiber reinforced concrete slabs. Different models are suggested considering the effect of concrete compressive and tensile strength, amount of flexural reinforcements, yield strength of the reinforcement bars and steel fiber properties (volume percent, aspect ratio, and type of steel fibers). The predicted results are compared with the experimental data found in literature and found good agreement.

Steel fiber reinforced concrete is used as a construction material in modern structures. Recent studies have shown that steel fiber can be used to improve the behavior of structures and increase the bending moment capacity and shear strength of reinforced concrete members.This research present and modify the nominal and ultimate bending moment equation, maximum and balance reinforcement indices and depth of compression zone for different types of reinforced concrete beams: single, double and T beams including the effect of steel fibers.The modified equations showed that the internal moment capacity of the beams with steel fiber increased by the amount ( ) which represent the participation of the steel fiber. The balance and maximum reinforced indexes ( & )decreased by ( ) for single, double & T-beam reinforced concrete, this means that the ductility increased by adding steel fiber. Also the depth of compression zone increased by a factor ( ) which is greater than (1.0). The modified equations are verified and applied on the reinforced concrete beams with steel fibers which tested in previous study, the theoretical results showed excellent agreement with the experimental values.

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Beam-column frame system and flat plate slab system are analysed by semi-empirical, Direct Design method (DDM) and approximate elastic method, Equivalent Frame method (FEM) and the results of both methods are compared with computer software based on Finite Element method (FEM), taking into account the effect of changing the beam and column stiffness and the panel length ratio, for 3, 4, and 5 equal span frames and three non-equal spans. The moment coefficients with respect to the maximum clear span moment are determined by the three methods for negative end moments at the face of support and mid span positive moment. These coefficients are constant in DDM, while in EFM are changed with changing the column and beam sizes. The results of EFM is more accurate than DDM, on the bases of results of EFM, new moment coefficients are suggested to use instead of DDM moment coefficients. In case of EFM calculation aren’t satisfactory for hand calculations the FEM is used by applying available computer software.