Stress Strain Relationship and Modulus of Elasticity of Normal and Steel Fiber Reinforced Concrete under Uniaxial Compression Pressure

Steel fiber reinforced concrete's stress-strain characteristics and compression elastic modulus are key in structural analysis and design. The purpose of this research is to explore the stress-strain behavior and modulus of elasticity of steel fiber reinforced concrete (SFRC) and normal concrete (NC) in order to experimentally assess their compression-stress behavior. The SFRC was reinforced with straight steel fibers with a nominal length of (13 mm), diameter of (0.2 mm), and aspect ratio (length of the fiber to the diameter of the fiber) was about (65). For the purposes of this experiment, the volume fraction was fixed to 1%, and normal concrete was used as a reference. When fiber is added to concrete, the ultimate stress, ultimate strain, toughness, and the modulus of elasticity were increased. As shown in an experiment, the SFRC had a very high values of strain capacity which was about (74.51%) more than that for NC, indicating that it had high ductility. Also a comparison was carried out between the experimental resultsof modulus of elasticity and the pervious theoretical proposed equations for SFRC and NC,the test resultsshowed a good agreement compared with the results of the theoretical equations.