Analysis and stiffeners' design of a steel bridge girder

Abstract

Plate girders are designed to carry massive loads over large spans. Flanges resist moment and web resists shear forces. Shear strength of steel girders having slender webs is much less than the yielding shear capacity. It is mainly due to the buckling of the web prior to reaching the yield strength of the material. Webs are generally reinforced with transverse stiffeners to increase their buckling strength. Stiffened webs resist shear also after buckling, which is called as post buckling strength. Tension field theories explain the formation of the post buckling strength and predict the stiffened web’s ultimate shear strength. Most design code provisions are set on tension field theories. There exists plenty of tension field theories proposed until today. This paper covers the design shear strength check and design flexural strength check and the stiffeners’ design of a steel girder specimen which was designed intentionally to fail in shear buckling. Analysis and stiffeners’ design were performed according to the provisions for load and resistance factor design (LRFD) in the ANSI/American Institute of Steel Construction (AISC) 360-16 - Specification for Structural Steel Buildings.