一般壳体结构大位移和大应变弹塑性有限元分析与损伤力学的某些应用

离散的Kirchhoff理论三角形单元对一般壳体结构的分析是十分可靠的和有效的，本文将推广此种单元去分析壳体结构的大位移大应变弹塑性响应，校正的拉格朗日增量的Jaumann应力公式和塑性损伤相耦合的塑性流动本构关系已应用于列式中，在对带环向裂纹和环向槽受四点弯曲载荷的圆醉壳的分析中，显示了和实验结果符合一致，且说明了与塑性损伤相耦合的大应变弹塑性分析无论在宏观水平上或微观水平上都能显示比断裂力学方法更符合实际的结果。

FINITE ELEMENT METHOD FOR LARGE DISPLACEMENT AND LARGE STRAIN ELASTO-PLASTIC ANALYSIS OF SHELL STRUCTURES AND SOME APPLICATION OF DAMAGE MECHANICS

The discrete Kirchhoff theory element is generalized on analyses of ordinary shell structures. In this paper, the element is used to analyse elasto-plastic response of shell structures of large displacement/rotation and large strain, where the updated Lagrangian incremental Jaumann stress formulation, and the flow theory of plasticity coupled with ductile damage aud Von Mises yield condition are adopted. The circumferentially through-wall cracked pipe as well as notched pipe under four-point bending load are analysed and compared with experimental data. A better agreement is achieved. Compared with the results of fracture:mechanics, not only at microscopic level but also at maoroscope level, the advantage of the new method for elasto-plastic analyses of the studied objects has been shown.