Formulas: Flange Local Buckling

Formula 1

M_{n}=M_{p}-\left(M_{p}-0.70 F_{y} S_{y}\right)\left(\frac{\lambda-\lambda_{p f}}{\lambda_{r f}-\lambda_{p f}}\right)

M_{n}=F_{c r} S_{y}

F_{c r}=\frac{0.70 E}{\left(\frac{b}{t_{f}}\right)^{2}}

\lambda=\frac{b}{t_{f}}

$\lambda_{p f}=\lambda_{p}$ , the limiting width-to-thickness ratio for a compact flange as defined in Table B4.1b

\lambda_{p f}=\lambda_{p}

$\lambda_{r f}=\lambda_{r}$ , the limiting width-to-thickness ratio for a noncompact flange as defined in Table B4.1b

\lambda_{r f}=\lambda_{r}