Multiaxial experiments with radial loading paths on a polymeric foam

Cellular materials such as polymeric foams in particular have been widely studied under uniaxial loading conditions. Many experimental studies have been focusing recently, however, on the responses of these foams to multiaxial loads. In the present study, a novel experimental hexapod device was used to perform combined uniaxial compression and simple shear tests. Using a post-processing method of analysis which can be used to study elementary mechanical behavior, the authors show the occurrence of non-proportional stress paths in the material under investigation although proportional kinematic paths were imposed. A failure limit criterion is presented for use with the foam of interest. The results of the present analysis yield useful information for meeting our future objective, namely to develop a numerical model for simulating multiaxial loading conditions.