SIMULATION OF ANISOTROPIC ELASTIC-PLASTIC BEHAVIOUR OF MATERIALS BY MEANS OF AN ISOTROPIC FORMULATION

S. OLLER; E. OÑATE; J. MIQUEL

Congreso; Second US National Congress on Computational Mechanics; 1993

This paper shows a generalization of the standard isotropic plasticity theory to be applied to any orthotropic or anisotropic material. This approach assumes the existence of two spaces: The rst one is named the real anisotropic space which denes the actual features of the problem to be solved. The second one is named ctitious isotropic space and here is where the mapped ctitious problem is solved. Both spaces are related by means of a lineartransformation using a fourth order tensor, named space change tensor, which contains all the information relating the real material properties and ctitious spaces.The principal caracteristic of this approach is its generality and capability to take advantage of the clasical isotropic elasto-plastic formulation and the correspounding nite element computational model.The paper describes the basis of the space transformation proposed and the expressions of the resulting non linear constitutive equations for anisotropic material. Also details of the numerical treatment of the resulting constitutive equation are provided. Examples of application showing the good performance of the model presented are nally given