Metallic fiber-reinforced concrete behaviour: Experiments and constitutive law for finite element modeling

Numerical model to predict the mechanical behaviour of concrete matrix reinforced with sliding metallic fibers is presented. Considering fiber-reinforced concrete (FRC) as two phase-composite, constitutive behaviour laws of plain concrete and fibers were described first and then they were combined according to anisotropic damage theory to predict the mechanical behaviour of metallic fiber-reinforced concrete. The behaviour law used for the plain concrete is based on damage and plasticity theories. The constitutive law of the action of fibers in the matrix is based on the effective stress carried by the fibers. This effective stress depends on a damage parameter related to on one hand, on the content and the mechanical properties of the fiber and on the other hand, on the fiber–matrix bond. The proposed model for FRC is easy to implement in most of the finite element codes based on displacement formulation; it uses only measurable parameters like modulus of elasticity, tensile and compressive strengths, fracture energies and strains at peak stress in tension and compression. A comparison between the experimental data and model results has been also provided in this paper.