Axial resistance of elliptical hollow section K-joints made of high strength steel: Fid-Bau Portal

Axial resistance of elliptical hollow section K-joints made of high strength steel

Ozyurt, E.

Abstract The present study examined the axial resistance of welded elliptical hollow section (EHS) K-joints made of high-strength steel (HSS). The axial resistance of EHS K-joints was affected by a range of factors, including the geometrical parameters, orientations, chord pre-stress levels, and the mechanical properties of the high-strength steel grades. This research aimed to investigate the performance of welded EHS K-joints made of HSS under axial loading conditions with or without chord pre-stresses. Finite element analysis was employed for numerical simulations to analyze the nonlinear behaviour of EHS K-joints with HSS. It was observed from the numerical results that the orientation types significantly affected normalised resistance ratios. In contrast, β, γ, θ, and chord pre-stress levels had minimal impact, as comparisons were based on normalised resistance ratios. However, non-dimensional geometric parameters and chord pre-stress levels notably influenced the axial joint resistance of the HSS K-joints. As for predicting the axial resistances of EHS K-joints with HSS, the numerical results indicated that the existing reduction factor might be unsafe for the equivalent RHS method to be applied in the current design guides. Therefore, a new reduction factor was proposed for EHS K-joints with HSS that yield unsafe results.

Highlights • This paper presents a numerical study completed on axial resistance of EHS K-joints made of HSS. • A range of geometrical parameters and chord pre-stress levels were examined. • The orientation types significantly affected the behaviour of EHS K-joint with HSS. • The β, γ, θ and chord pre-stress levels had minimal impact on the joint normalised joint resistance. • A new design method is proposed to predict the capacity of the EHSK-joints with HSS.