Deformation of composites with arbitrarily oriented orthotropic fibers under matrix microdamages

Анотація

In the present paper a model of nonlinear deformation of stochastic composites under microdamaging is developed for the case of composite with orthotropic inclusions, when the microdamages are accumulated in the matrix. The composite is treated as an isotropic matrix strengthened by three-axes arbitrarily oriented ellipsoidal inclusions with orthotropic symmetry of elastic properties. It is assumed that the loading process leads to accumulation of damages in the matrix. Fractured microvolumes are modeled by a system of randomly distributed quasi-spherical pores. The porosity balance equation and relations for determining the effective elastic modules for the case of orthotropic components are taken as basic relations. The fracture criterion is assumed to be given as the limit value of the intensity of average shear stresses occurring in the undamaged part of the material. Basing on the analytical and numerical approach an algorithm for determination of nonlinear deformative properties of such a material is constructed. The nonlinearity of composite deformations is caused by finiteness of deformations. Using the numerical solution the nonlinear stress-strain diagrams for an orthotropic composite for various cases of orientation of inclusions in the matrix are predicted and discussed.