Behavior of steel tension members subjected to uniaxial loading

Current design specifications for statically loaded tension members do not consider the bending effects due to connection eccentricity. However, recent experimental investigations have shown that connection eccentricity induced bending effects have the potential to significantly reduce the net section rupture capacity of a section. This study focuses on examining the effects of connection eccentricity and connection length on the ultimate capacity of bolted WT tension members. In particular, complementing prior experimental investigations by the authors and others, the main objective of this work is to develop robust finite element tools capable not only of estimating the failure loads but also to trace the entire load versus deflection path. In this study, the finite element analysis (FEA) of the WT section is carried out using eight node incompatible hexahedral elements (ABAQUS C3D8I element) capable of representing large deformation geometric and material nonlinearities. The connecting bolts are assumed to be rigid and a surface-to-surface contact is used to fully transfer the load from the gusset plate to the web. An elasto-plastic von Mises yield criterion combined with a tri-linear type constitutive model is used to represent the material nonlinear effects. The load corresponding to the load limit point is taken as the failure load of the WT specimen.Results of the finite element analyses are compared with experimental results, code predictions, and analytical predictions of the section capacity. The failure capacities predicted by the FEA are in excellent agreement with the experimentally observed failure capacities of the WT sections subjected to tensile loading.