Deformation of orthotropic composites with unidirectional ellipsoidal inclusions under matrix microdamages

Анотація

In the present paper a model of deformation of stochastic composites under microdamaging is developed for the case of orthotropic composite, when the microdamages are accumulated in the matrix. The composite is treated as an isotropic matrix strengthened by three-axial 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 modelled 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 the composite with orthotropic components are taken as the 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 the algorithm for determination of nonlinear deformative properties of such a material is constructed. The nonlinearity of composite deformations is caused by accumulation of the microdamages in the matrix. Using the numerical solution the nonlinear stress-strain diagrams for orthotropic composite for the case of biaxial extension are obtained.