Identification of material parameters using bi-axial machine

Experimental testing equipment is built in order to identify material parameters of complex phenomenological constitutive laws. This equipment consists in a bi-axial test machine able to perform plane strain and simple shear tests separately or simultaneously and a Miyauchi simple shear test device; an optical extensometer is used to identify the strain field. The article focus on the validation of the results of this new equipment by comparing with results obtained by standard machines and/or by using FEM simulations of already identified materials. The first results show that the bi-axial machine performs the plane strain test optimally and some modifications are proposed in order to improve the results for the simple shear test. Miyauchi device shows a good performance and the experimental results are compared with a FEM simulation.