We propose a multiscale model for FRC composites that is a combination of semi- analytical and computational sub-models specified at multiple scales. At the scale of the single fiber, a semi-analytical model is developed that characterizes the microslip behavior at…
We propose a multiscale model for FRC composites that is a combination of semi- analytical and computational sub-models specified at multiple scales. At the scale of the single fiber, a semi-analytical model is developed that characterizes the microslip behavior at the interface between the matrix and the fiber in terms of the overall composite stresses. The influence of fiber bundles on microcrack bridging and arrest is taken into account within the framework of the linear elastic frac- ture mechanics. Upscaling to the macroscopic level is achieved by using continuum micromechanics. Weshowthatthemacroscopicdeformation of the FRC composite is governed by a ’TERZHAGI’ like effective stress. Selected numerical experiments provide insight into the role of the interface property, resulting on the macroscopic level - in a brittle, softening behaviour in case of weak bond and a rather ductile, hardening behavior in case of a relatively strong interface bond that is completely described by simple microslip laws. For the finite element analyses of failure behavior at the structural level, the so-called ’interface solid element’ (ISE) is used to represent the cracking process. The softening behavior of ISE is governed by the crack bridging law obtained above. The implicit-explicit integra- tion scheme is implemented to enhance the robustness of computation.