Numerical and experimental analysis of post-critical deformation states in a tensioned plate weakend by a crack

The paper presents the methodology of determination of the stress distribution in post-critical state of deformation of the rectangular plate weakened with the crack subjected to tension. The problem was formulated as physically and geometrically non-linear. Using the finite elements method, numerical analyses were performed. While solving the nonlinear issue, the progressive change of geometry of the structure in successive incremental steps were compared with results of experimental studies, performed simultaneously. The obtained results made the base for the assessment of reliability of effects of nonlinear numerical analysis, conditioned by the presence of imperfections of the plate in the neutral state. Two kinds of imperfections were considered: geometric - based on the assumption of the preliminary deflection of the plate in the zone of weakness and the second one – in form of load perturbation, normal to the middle surface of the plate.