Experimental and numerical investigation of steel fiber concrete fracture energy

Abstract

This research investigates the influence of steel fibers on the mechanical properties and behavior of concrete through a combination of numerical simulations and laboratory experiments. A series of numerical models were developed and validated against experimental results, employing circular-shaped aggregates to ensure model accuracy. The load-CMOD diagrams revealed that an increase in the percentage of steel fibers led to significant improvements in the tensile strength and energy absorption of the concrete specimens. The presence of steel fibers acted as an effective barrier, inhibiting crack propagation and enhancing the energy absorption capacity of the concrete. However, beyond a certain fiber percentage (approximately 4%), the increase in energy absorption became limited due to reduced bonding forces between the fibers and cement mortar, resulting in premature failure of the specimens. The numerical models provide valuable insights into the behavior of fiber-reinforced concrete, facilitating the optimization of concrete design for various engineering applications. This study contributes to a broader understanding of fiber-reinforced concrete behavior and underscores the significance of selecting the optimal fiber content and distribution for specific construction scenarios. Further research is encouraged to explore the complex mechanisms of fiber-matrix interaction in concrete for developing more resilient and durable concrete structures.