Multiscale modeling and simulation on mechanical behavior of fiber reinforced concrete

A multiscale mechanical model is proposed to quantitatively describe the macro-mechanical behavior of fiber reinforced concrete (FRC) based on its multiscale material compositions. Firstly, according to the actual scale characteristics of compositions, the model of composite material at each scale of FRC, including hardened cement paste, cement mortar and meso-FRC, was geometrically reconstructed; Secondly, the equations of stiffness and strength of composite material at each scale were established by using the equivalent inclusion theory and Ottosen failure criterion, and a multiscale mechanical model of FRC was proposed by upscaling from stiffness and strength of microstructure to macro-mechanical behavior of FRC; Finally, after verified by the experimental results in the literature, the proposed model was used to numerically investigate the loading-induced stress response and the evolution of macro-mechanical properties of FRC in its curing process, as well as the influence of steel fiber parameters, such as volume fraction, aspect ratio and spatial orientation, on the mechanical properties of FRC.