増分非線形モデルの数学的構造・定式化と主応力軸回転時の挙動の検証

抄録

The incrementally nonlinear behaviors of engineering materials, in particular geomaterials, are often reported and formulated into constitutive models. We here discuss the mathematical structure of incrementally nonlinear constitutive models among stress rates, strain rates, and the rate of change in internal variables through the representation theorem of isotropic functions and their matrix forms. As the examples of incrementally nonlinear models we discuss the formulation of the multi-slip model and the modified elasto- plastic model leading to incremental nonlinearity. Both models are evaluated whether they can account for the behavior of sands during the rotation of principal stress axes and found to be satisfactory from a qualitative view point.