The thesis consisted in the development of two transversely-isotropic elastic–plastic constitutive models for unidirectional fiber reinforced polymers.
Both these models are able to represent the fully non-linear behaviour under multi-axial loading conditions.
Moreover, an anisotropic pressure-dependant yield function and a non-associated plastic potential function, are assumed in order to model realistic plastic deformations.

The models were then implemented in the commercial finite element software ABAQUS/Implicit, for which two UMAT (user defined material subroutines) in FORTRAN had been developed.