Concrete behaves as a quasi-brittle material under mechanical loading and it has been identified as a particulate composite with several identifiable phases at its mesoscopic level. However, for the purpose of numerically simulating the compressive response, the material can be visualized as consisting of mainly three phases viz, a matrix phase, an aggregate phase and a transition phase. A unit cell based approach is followed in the present work to model the nonlinear deformation and failure response of mixed fiber reinforced concrete under compressive loading. Once the necessary boundary conditions are applied on the boundaries of the unit cell and all the required implementation procedures are carried out, parametric studies can be conducted on the three-phase unit cell to successfully capture the full non-linear deformation and failure response of the material under compression.

Keywords: Representative volume element, Compression response of concrete, Interfacial transition zone, Mixed fiber reinforced cement composite, Unit cell approach.