Extended concept of representative directions to describe inelastic behaviour of electrospun polymers

The concept of representative directions allows one to generalize onedimensional uniaxial material models to more general constitutive equations, suitable for arbitrary multi-axial loading scenarios. The procedure preserves the thermodynamic consistency and the resulting material model satisfies the principle of objectivity. In the current paper, the concept is modified by the introduction of new kinematics. Some features of the resulting constitutive equations as well as the applicability of the extended concept to real materials are discussed. For demonstration purposes, the plastic behaviour of an electrospun polymer is modelled under large strain non-monotonic loading.