Steel box girder has not only an excellent constructability but is also a lightweight structure. Compression flanges of steel box girder under negative moment need stiffeners to increase buckling strength, thereby increasing the construction cost. In this study, compression flanges using trapezoidally bended plates were investigated to replace existing flat flanges.

Shin Geo-Je Bridge needs new inspection holes to improve the accessibility for various maintenances. This study evaluated the maximum effective stresses of the bottom flange when the inspection holes is made with an ellipse shape. The FEM analysis results show that the inspection installation is possible to the inflection point of the girder.

Shin Geo-Je Bridge needs new inspection holes to improve the accessibility for various maintenances. This study evaluated the maximum von mises stresses(SE) of the bottom flange when the inspection holes is made with an ellipse shape. The FEM analysis results show that the inspection installation is possible to the inflection point of the girder because buckling phenomenon doesn't occur according to the loading.

Shin Geo-Je Bridge needs new inspection holes to improve the accessibility for various maintenances. This study evaluated the maximum von mises stresses(SE) of the bottom flange when the inspection holes is made with an ellipse shape. The FEM analysis results show that it is reasonable the hole is installed near the inflection point of the girder from a structural safety point of view though additional cost for the inspection walkway

압축플랜지의 설계는 단순히 종방향 보강재와 횡방향 보강재로 둘러싸인 서브패널(sub-panel)의 극한거동에 대해 적절한 안전율을 도입하여 이루어져 왔다. 그러나, 종방향 보강재의 수와 강성, 횡방향 보강재의 간격, 초기 변형량과 잔류응력의 분포 등 제 영향을 고려해서 압축플랜지 전체의 극한강도를 결정하는 것이 합리적이다. 본 연구에서는 Folded Plate 이론에 근거하여 압축플랜지에 대해 기하강성의 영향, 재료적 비선형성을 고려한 해석 프로그램을 개발하고 이를 바탕으로 국내에서 실제 시공된 강박스거더교의 압축플랜지에 적용하였다.