ABSTRACT
Anatomical studies have shown that cardiac tissue has the strong anisotropic behavior. Therefore it needs for new constitutive equations with anisotropic hyperelasticity. A general framework for explicit constitutive relations suitable for fibre reinforced hyperelasticity is derived for invariant-based material models both, for the reference and the current configuration. MSC.Marc can be used in extensively rubber industries, however, does not adopt the transversely isotropic hyperelasticity. The program implementation is based on the updated Lagrange formulation. It is required to reshape few internal source codes. User subroutine UELASTOMER can be used to define a general strain energy function in the updated lagrangian framework. It can be used for transversely isotropic hyperelastic to coalesce internal and external subroutine. Another test is a simple square plate which is compressed by a rigid body. The compression ratio is 40%. Two analyses are performed, one material is conventional Mooney-Rivlin hyperelastic, and the other is reinforced in the horizontal direction.
