This study numerically investigates buckling behavior of press braked steel plates with a free edge. In order to improve structural stability during construction, the top flanges of press-braked U section girder are laterally braced by the installation of prefabricated half-deck. Thus, an unbraced length is taken as the longitudinal spacing of pockets on the half-deck, which are to make composite section. This study performed 3D finite element analyses to evaluate an equivalent effective width of cold-formed flange with a free edge. Through the parametric numerical analyses, the elastic buckling stresses of the cold-formed flanges with rounded corner in the cross-section were compared with those of general flat plates. Then, the equivalent effective width of the cold-formed (press-braked) flanges were numerically examined for some representative cases.

1. 반구형 각의 분포 및 집중하중에 의한 좌굴응력 해석은 변형된 각의 형상에 따라 타원체 각의 응력으로 해석함이 타당하다. 2. 일정 한계이상의 형상계수를 갖는 반 구형각에 대하여서는 재료상수를 형상계수의 승수로 고려한 수정된 임계좌굴 하중으로 탄소성 좌굴을 판정함이 더 양호한 결을 준다. 3. 탄소성 좌굴에 있어서 소모된 소성변형 에너지를 계산하기 위하여 항성변형 에너지를 계산하기 위하여 항상선를 따르는 에너지법을 이용하면 양호한 결과를 얻을 수 있다.

Corrugated plate is made that the local buckling, global buckling and interactive buckling occurs because of the geometric properties such as the accordion effect.Corrugated steel having such characteristics is shows a buckling characteristic different from the plate. However, It was a design by the basis of the shear buckling equation of plate. Therefore, this study was investigate the characteristics of the shear buckling mode and shear buckling stress of sinusoidal corrugated plate through a parametric study using the finite element method.