抄録
In this paper, a finite element method is applied to a large deflection analysis for the postbuckling behavior of plate elements of structural members. In order to avoid the numerical integration process and to improve the numerical procedure, a constant strain and curvature element is used and the rigid body motion of the individual elements is excluded. The in-plane torsional stiffness is introduced using assumptions based on the micropolar theory to avoid actual or near singularity of the global stiffness matrix and divergence of the numerical solution. The versatility and efficiency of the present method is illustrated by several examples. The numerical results indicate that the present method enable to pursue the postbuckling behavior of plate elements of structural members even in the range of very large deflection. In the plane of the web plate, deflections of the line junctions between intersecting plate elements or those of the unloaded edges become very large in the more advanced postbuckling range, and it is shown that the strength of the member or the plate element decreases in the case of elastic problems.
