Effect of material nonlinearity on progressive damage of laminated composites

The progressive damage of laminated composite with a circular hole subjected to tensile loading was analyzed with finite element method in terms of Hahn-Tsai nonlinear shear stress-shear strain relation. The mode and criterion of the damage were presented. The improved Newton-Chsicer method was used to the nonlinear iteration. The results of simulation calculation show that considering effect of nonlinearity of the material, the accuracy of the calculation may be enhanced, especially for orthotropic laminate, and the variance of nonlinearity coefficient has more serious effect on orthotropic plate than on quasi-isotropic plate.