Local Elasto–plastic Buckling of Isotropic Plates With Cutouts Under Tension Loading Conditions

The motivation of the presented study was the observation of the existence of local loss of stability “tension buckling” in the experimental tests of composite and metallic plates with cut-outs subjected to tension. Because of this, the numerical analyses of the aluminum plate with elliptical or circular cutouts at the center and subjected to tensile load are studied in the paper. Although the whole structure is uniformly stretched, the circumferential compressive stresses in the vicinity of the cutout edge are observed. First of all, the linear buckling analysis is carried out for different sizes of the holes. Based on these results, the size of the hole is chosen, where the circumferential stress magnitude in the vicinity of the cutout is the lowest or even comparable to the yield stress of the material. The computations are made for three different values of thickness. Finally, the nonlinear buckling analysis is carried out without and with the plasticity effects included. Generally, in the case of the circular and vertically oriented elliptical cut-out, the loss of stability in the tensed plate is always observed. However, in elastic-plastic analyses, the values of the critical parameters significantly differ from the results obtained for elastic buckling. Finally, the critical geometries for further experimental tests were defined.