“…Much research has been done on traditional macro-continuum inelastic constitutive modeling such that a wide range of books are available to reference (Hill, 1950;Desai and Siriwardane, 1984;Lubliner, 1990;Maugin, 1992;Simo and Hughes, 1998;Simo, 1998;NematNasser, 2004). Likewise, research has been done and is ongoing on simulating directly the inelastic microstructural mechanical response-at the grain/particle/fiber scale-and reported in the literature (e.g., for polycrystalline metals (Vogler and Clayton, 2008), ceramics (Maiti et al, 2005;Molinari and Warner, 2006;Sadowski et al, 2007), concrete (Caballero et al, 2006), masonry (Formica et al, 2002), geomaterials (soils (Nezami et al, 2007) and rocks (Morris et al, 2006)), asphalt (Birgisson et al, 2004;Dai et al, 2005), bone (Chevalier et al, 2007;Lee et al, 2007)). One of the current research challenges, however, is how to bridge these length scales, from grain/particle/fiber scale (sometimes called the 'meso'-scale) to the macro-continuum scale of the engineering application, without losing salient kinematic structure and micro-stresses.…”