ИСТИНА

In order to study an influence of nonlinear plane shear stiffness phenomena on damage and failure, a problem of a laminated composite open hole plate subjected to compressive load was considered. Layup [(±45)6]S with expressive nonlinear loading diagram, caused by nonlinear elastic shear stiffness of the composite material, was analyzed. Constitutive equations taking into account nonlinearity of the shear stress–strain relations were used in combination with a damage model based on degradation parameters. The predicted loading diagram has demonstrated a good agreement with experiment for both loading phases with pristine composite plate and after damage initiation. Stress fields comparison of the linear model using constant shear modulus and true nonlinear shear one was performed. Despite an accurate prediction of failure load values obtained by both models, the damage parameter distributions show significant difference.