Investigation on Mode ? I Fracture Parameters Using Steel Fibers in High Strength Concrete

Steel fiber high-strength concrete (SFHSC) become in recent decades a very popular material in structural engineering. As a result of increased application of SFHSC, many experimental studies are conducted to investigate its properties and develop new rules for proper design. It has been confirmed by many authors that the specific fracture energy of concrete determined by laboratory experiments depends on the shape and size of the specimen because the local energy in the fracture process zone is influenced by the free surface of the specimen. Mode-I crack propagation in SFHSC is simulated by fracture mechanics. This work aims in studying the mechanical behavior of concrete in terms of modulus of elasticity with the change of aggregate size reinforced with steel fibers of different series for SFHSC concretes. Experiments include compression tests and split tensile strength tests. Study on effect of volume fraction of fibers and change of aggregate size on the modulus of elasticity of concrete was also deemed as an important part of present experimental investigation. The results obtained show that the failure stresses, stress intensity factor, fracture energy and in addition of steel fiber improves the modulus of elasticity of concrete.