逆解析を用いた種々の溶接継手における固有変形の同定

抄録

Inherent deformation method, in which the inherent deformation is introduced into the elastic FEM as the initial strain, is one of the effective methods to predict welding deformation of large structures, such as ships, bridges and automobiles. When the welding length is long enough, the inherent deformations namely, longitudinal shrinkage, transverse shrinkage and angular distortion are mainly governed by the heat input Q and the thickness of plate h. When the welding length is short, the inherent deformations are also influenced by the length of weld. In order to estimate inherent deformations for short welding, an efficient measuring method to obtain inherent deformation of plate under bead welding using inverse analysis was developed. Base on this inverse analysis, the inherent deformations are estimated by measuring the three-dimensional coordinates at a small number of selected points before and after welding. In this paper, the application of inverse analysis to typical welded joints, such as butt joint, lap joint, T-joint is discussed. By comparing the values of deformation components calculated by using the measured coordinates and those using inverse analysis, the effectiveness of the inverse analysis is confirmed. Then, reliability of the database for butt weld joint build by inverse analysis is also discussed in this paper.