Homogenization of heterogeneous polymers

Conventional homogenization methods are based on the assumption that the material is statistically homogeneous[ However\ if a material exhibits strain softening behaviour and localization of deformationthis assumption is no longer valid[ The obvious solution is to extend the state of the material point with additional statistical moments of the state of the RVE[ When long range e}ects are incorporated into the continuum mechanical description of the material\ in the form of supplementary degrees of freedomthese so!called non!local models are capable of describing strain softening[ In this paper\ a perforated polycarbonate plate is used as a model material[ The mechanical behaviour of the RVE will be described by using a compressible Leonov model\ which accounts for the time dependent\ large strain behaviourcharacteristic for solid polymers[ At the macroscopic level\ non!linear elastic Cosserat mechanics is applied for the equivalent homogeneous material[ It is shown to be possible to determine the macroscopic constitutive equations for the equivalent continuum[ As application\ a tensile test on a single edge notched specimen will be discussed and compared to {direct simulations