Postbuckling behaviour of laminated plates with a cut-out

The subject of research is the numerical and experimental analysis of a thin-walled plate with the cut-out, made of the laminate and subjected to the axial compression. In order to ensure the stable plate work in the postcritical range, it need to force its work by higher flexural-torsional form of buckling. The scope of the research included nonlinear numerical analysis with Finite Element Method (FEM) and experimental verification of calculation results. For the composite material in numerical calculations, the model of orthotropic material in the flat state of tension was defined. For the mapping of the plate element coating finite elements of type SHELL was applied with a shape function of the second order to allow the mapping of the composite structure for the element thickness. The experimental research was carried out in a special grips providing the articulated support of the upper and lower edges of the plate. The deformation registration of compression structures were carried out with resistance extensometry. This allowed to define of postcritical equilibrium paths of real structure, showing the dependence of the force to displacement. The instrument used was a numerical program ABAQUS®.