发展Ｖｌａｓｏｖ半无矩壳理论用于轴压棱柱形壳体弹塑性稳定性分析，其中本构关系采用形变理论．通过对双对称单闭室箱梁的分析，揭示出轴压棱柱形壳体弹塑性稳定性特征：棱柱形壳体剖面畸变不能忽略，在一定尺度范围内最小失稳载荷对应于畸变失稳；考虑塑性影响，弹性变形范围内的畸变失稳可能会转化为塑性范围的弯曲失稳． The development of Vlasov semi-moment-free shell theory is used to analyze the elasto-plastic stability of axial compression prismatic shells. The deformation theory is used for the constitutive relationship. The analysis of the elasto-plastic stability of the axially-compressed prismatic shell reveals that the distortion of the prismatic shell can not be neglected. The minimum destabilizing load within a certain scale corresponds to the distortion instability. Considering the plastic effect, the distortion instability in the range of elastic deformation may be transformed into the bending instability in the plastic range.