本文提出了在轴向力、弯矩、扭转及内压联合载荷作用下含周向裂纹管塑性破坏载荷的力学模型。按ＶｏｎＭｉｓｅｓ准则可确定塑性跨塌时净截面上诸正应力值，进一步又给出了各种裂纹管道（诸如表面裂纹、穿透裂纹等）的诸塑性极限载荷表达式。本文对缺陷评定十分有用。 In this paper, a mechanical model of the plastic failure load of a circumferential cracked tube under combined axial load, bending moment, torsion and internal pressure is proposed. According to the Von Mises criterion, the normal stress values ​​on the net section of the plastic collapse can be determined, and further the plastic limit loads expressions of various crack pipes (such as surface cracks, penetration cracks, etc.) are given. This article is useful for defect evaluation.