POLYMORPHIC CONSTITUTIVE-EQUATIONS IN FINITE-ELEMENT CODES

This work presents an object-oriented design approach to the programmi ng of finite element constitutive equations. A universal interface for arbitrary material laws is introduced from which easy addition and ex pansion of the material library can take place. Although such expansio n using a generic interface is by definition polymorphic, the idiom is carried much further in several aspects of program design. Deriving f rom abstract examples of equation and algorithmic encapsulation, simpl e elastic damage and complex inelastic constitutive laws are developed . Examples of calculations show that adequate performance is given by C++ with respect to FORTRAN77 for simple to very complex material laws . The performance is seen to be a much stronger function of the compil er used than the actual numerical complexity.