Local joint flexibility of tubular K-joints reinforced with external plates under out of plane bending moments

Abstract

ABSTRACT In this research work, the Local Joint Flexibility (LJF) of steel tubular K-joints reinforced with external plates is investigated. In the first step, a finite element (FE) model was generated and verified. In the next step, a set number of 300 FE analysis was carried out to investigated the effect of the stiffener plate size (η and λ), the angle between brace and chord (θ), the joint geometry (γ, τ, ξ and β) and the loading conditions (balanced and un-balanced OPB moments) on the LJF factor (f LJF) and f LJF ratios (ψ). The results showed that the f LJF of an external plate reinforced K-joint can be down to 26% of the f LJF of the corresponding un-reinforced joint. Also, the gap factor (ξ) has effect on the f LJF. Finally, FE results were used to derive two parametric equations for determining the f LJF in the strengthened K-joints.