Accurate prediction of shear buckling capacity of low-yield-strength steel considering plastic deformations

Owing to a high plastic deformation capacity, low-yield-strength steel (LYS) shear panel dampers have been widely used in structural seismic engineering. Meanwhile, there is still no effective method to evaluate the shear buckling capacity of LYS shear panel dampers under plastic deformation. Thin-walled cylinders approximated as shear panels are adopted to experimentally analyse the plastic buckling. The effects of the shape aspect ratio and the width-to-thickness ratio on the deformation capacity are discussed. The buckling behaviour is directly judged and analysed by measuring the out-of-plane deformation of the specimens. By analysing different plastic modulus during buckling, it is found that the critical plastic buckling stress can only be predicted accurately when the variable deformation theory incorporated with the stable plastic deformation is adopted. The critical buckling strain of the LYS can be evaluated by the width-to-thickness ratio solely. This study will be of significant value in the analysis of the buckling capacity of LYS in the plastic-deformation range.