Homogenized nonlinear constitutive properties and local stress concentrations for composites with periodic internal structure

Abstract A unit cell problem governing effective mechanical properties and local stress concentrations for composites with periodic micro-structure and nonlinear constituents has been derived by employing an asymptotic expansion of the field variables in two length-scales. The influence of cell type upon effective properties has been investigated for a continuous fiber reinforced composite. It was found that the effective transverse properties are strongly dependent on the unit cell type when the matrix exhibits a nonlinear response. Finally the anisotropic behavior of the hexagonal unit cell and its applicability to determine effective properties and initial yield surface for transversely isotropic composites has been investigated.