An extended evaluation for the shear behavior of hollow tubular flange plate girders

In this paper, an extended numerical investigation is conducted to study the shear behavior of transversely stiffened hollow tubular flange plate girders (HTFPGs) using ABAQUS software. A comparison between the HTFPGs and plate girders with flat flange plates (IPGs) is first made considering the elastic-buckling and the post-buckling strength. The results indicated that the realistic support condition at the juncture of the web and flanges of HTFPGs is nearly fixed. The study is then extended to examine hybrid HTFPGs (HHTFPGs). The main goal of this extension was to examine the validity of the current EN 1993-1-5 provisions regarding both the shear resistance and the behavior trend of such hybrid girders. The validity of the other international design codes such as the AASHTO, AISC and BS 5950 were also checked. The results of the finite element (FE) models confirmed that using HHTFPGs provides economy as their strength could be utilised efficiently. In addition, it was found that the strengths obtained with EN 1993-1-5 provisions do reproduce suitably the trends obtained numerically, but their design equations were found to be extremely conservative. Moreover, the shear strength recently proposed for homogenous HTFPGs seemed to be slightly conservative for the case of HHTFPGs. Therefore, it was modified herein by taking the relative effect of the actual flange yield strength into account. This shear strength currently modified is found to represent the actual behavior of these girders better than the original and recently proposed EN 1993-1-5 shear strengths. Several remarks regarding the selection of optimum dimensions for the HTFPGs are also presented.