抄録
When steel structures are constructed by welding, welding distortion and residual stress (hereafter welding imperfection) are inevitably generated. It was verified in our studies that welding imperfection was predicted with high accuracy by thermal elastic-plastic analysis based on the infinitesimal deformation theory. On the other way, in the case that the ultimate strength of thin plate with the welding imperfection is predicted, elastic-plastic (hereafter El-Pl) analysis based on the large deformation theory with up-date Lagrangian method is generally carried out. However, it was known that the welding imperfection could not be reproduced by the unbalanced forces caused by the differences with both analysis theories when the welding imperfection was introduced into El-Pl large deformation analysis. Therefore, thermal El-Pl large deformation analysis program was developed. From the analysis results, it was elucidated that prediction accuracy of welding distortion was very low by thermal El-Pl large deformation analysis and that it took very long CPU time to predict welding residual stress by it.
