Identification of low density polyurethane foam properties by DIC and the virtual fields method

This paper deals with the identification of the mechanical behavior of low density polyurethane foam using digital image correlation (DIC) and the virtual fields method (VFM). First the so-called Iosipescu like bending/flexion tests in range of elastic deformation are presented, the elastic parameters will be extracted by a matlab toolbox called CAMFIT (download for free from www.camfit.fr), developed by authors' LMPF research group. Then the material in great deformation behavior is studied by a regular compression test on a rectangular block specimen. Many steps of load and deformed surface of the specimen will be recorded. The Ogden's law is applied to descript the kind of property. For all these kinds of tests, the full displacement fields are calculated by DIC software CORRELI, and the parameters will be achieved by using the virtual fields method.