Summary: | 碩士 === 中華技術學院 === 飛機系統工程研究所 === 97 === The paper presents the elastic-plastic analysis of plastic limit pressure of thick-walled hollow tubes under pressure involving plastic anisotropy and strain hardening. The hollow tube is assumed in plane-strain conditions and made of materials described by Hill’s yield criterion and the Voce hardening law. In this study, the finite-element computer code ABAQUS is utilized to perform the elastic-plastic analysis.
First, the numerical model is validated rigorously with comparisons between elastic-plastic results and analytical solutions based on the theorems of limit analysis. We consider thick-walled circular cylinders under internal pressure. Due to axis-symmetry of geometry and loading, the numerical analysis is based on an axial symmetric model. Numerical examples were conducted by considering transversely isotropic materials and planar anisotropic materials, respectively, with or without the strain-hardening properties. Good agreement is obtained to ensure the validity of the elastic-plastic analysis involving plastic anisotropy and strain hardening.
Finally, the above-mentioned numerical model is extended to consider hollow tubes with various cross section shapes with the same material, weight and thickness. Numerical examples with circular cross sections, square cross sections and triangular cross sections are performed to investigate the corresponding plastic limit pressure. Conclusions and suggestions for practical applications are provided.
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