Dynamic pre-processing software for the hyperviscoelastic modeling of complex anisotropic biological tissue materials

Soft biological tissues are complex structures with intricate microstructure, which is usually highly anisotropic. These tissues are typically composed of multiple fiber bundles, which may have a unique orientation, defined for each single element in a large finite element mesh for modeling complex structures such as the human heart. These complex orientations can be difficult to define in an ABAQUS input deck using existing methods. In general, each change in fiber orientation requires a “new material” to be defined. Using the conventional method of defining material properties in ABAQUS is time consuming and, as a result of the large number of input constants required, is prone to errors. It is therefore deemed desirable to create a new means of material property input. The ∗∗CC Cards method presented partitions the material property data for a time-dependent, anisotropic, material response into discrete card images, and thus eliminates much of the redundant data input required by ABAQUS. This strategy is also more efficient, both computationally and from the viewpoint of user time required.