Theoretical Study of The Occurrence Limit of Strain Nonuniformity in Cylinders, based on the Prediction of In-plane Bifurcation

对承受恒定轴向压力和循环扭转的弹塑性薄壁圆筒进行了滞回性能数值分析。结果表明，在轴向压缩过程中，出现了与轴向压缩不同的变形模式，这些变形模式引起了应变不均匀性的快速增长。将预测这一现象的理论推广到交变塑性区，并编制了数值分析程序。由于这种现象类似于内部屈曲，因此对其进行了有限元分析。

Hysteretic behavior numerical analysis has been carried out for elastic-plastic thin-walled cylinders subjected to a constant axial compressive force and cyclic torsion. It has been shown that various deformation modes appear, which are different from those under the constant axial contraction, and that those modes cause rapid growth of strain nonuniformity. Also the theory for predicting this phenomenon has been generalized to the alternating plasticity region and the numerical analysis program has been developed. Since this phenomenon is analogous to internal buckling, finite element analysis for it has been performed.