Description
In this chapter, component-based finite element method (CBFEM) of a fillet weld connecting a plate to an unstiffened column is verified on component method (CM). The steel plate is connected to the open and box section columns and loaded in tension.
Analytical model
The fillet weld is the only component examined in the study. The welds are designed according to Chapter 4 in EN 1993-1-8:2005 to be the weakest component in the joint. The design resistance of the fillet weld is described in Section 4.1. The force applied perpendicular to a flexible plate, which is welded to an unstiffened section, is limited. The stresses are concentrated in an effective width while the weld resistance around the unstiffened parts is neglected, as shown in Fig. 4.5.1. For an unstiffened I or H section the effective width is obtained according to:
\[ b_\mathrm{eff} = t_\mathrm{w} + 2s + 7kt_\mathrm{f} \qquad (4.5.1)\]
\[ k = \frac{t_\mathrm{f} \cdot f_\mathrm{y,f} }{ t_\mathrm{p} \cdot f_\mathrm{y,p}} \qquad (4.5.2)\]
The dimension s is for a rolled section \(s =r\) and for a welded section \(s = \sqrt{2} \cdot a \) . For a box or channel section, the effective width should be obtained from:
\[ b_\mathrm{eff} = 2t_\mathrm{w} + 5 t_\mathrm{f} \quad \textrm{but}\quad b_\mathrm{eff} \leq 2t_\mathrm{w} + 5 kt_\mathrm{f}\qquad (4.5.1)\]
\[\sqrt{ \sigma_{\perp}^2 + 3 \cdot \left( \tau_{\perp}^2 + \tau_{\parallel}^2\right)} \leq \frac{f_u}{\beta_{\mathrm{w}} \cdot \gamma_{\mathrm{M2}}}\]
\[\sigma_{\perp} = \tau_{\perp} = \frac{\sigma_{N}}{\sqrt{2}} = \frac{N}{b_\mathrm{eff} \cdot a}\cdot \frac{1}{\sqrt{2}} \]
\[ \tau_{\parallel} = 0\]
\[ \sqrt{ \left( \frac{\sigma_{N}}{\sqrt{2}} \right)^2 + 3 \cdot \left( \frac{\sigma_{N}}{\sqrt{2}} \right)^2} \leq \frac{f_u}{\beta_{\mathrm{w}} \cdot \gamma_{\mathrm{M2}}}\]
\[ \sqrt{ \left( \frac{N}{b_\mathrm{eff} \cdot a}\cdot \frac{1}{\sqrt{2}} \right)^2 + 3 \cdot \left( \frac{N}{b_\mathrm{eff}\cdot a}\cdot \frac{1}{\sqrt{2}} \right)^2} \leq \frac{f_u}{\beta_{\mathrm{w}} \cdot \gamma_{\mathrm{M2}}}\]
