A NUMERICAL EXPERIMENTAL-METHOD FOR A MECHANICAL CHARACTERIZATION OF BIOLOGICAL-MATERIALS

For the determination of material parameters, it is a common practice to extract specimens with well-defined geometries. The design of the s amples and the choice of the applied load are meant to lead to a homog eneous stress and strain distribution in a part of the sample. When ap plied to biological materials, this raises a number of problems: homog eneous strains cannot be obtained because the materials have inhomogen eous properties, and the manufacturing of samples is hard or sometimes impossible. In this technical note a different approach is presented, based on the use of a digital image technique for the measurement of nonhomogeneous strain distributions, finite element modeling and the u se of a minimum-variance estimator. The method is tested by means of e xperiments on an orthotropic elastic membrane of a woven and calendere d textile. Five parameters are identified using the experimental data of one single experiment.