P$.16\mathrm{.}5$ A thin$-$walled beam has the cross$-$section shown in Fig. P$\mathrm{.}16\mathrm{.}5.$ If the beam is subjected to a

bending moment $M_x$ in the plane of the web $23,$ calculate and sketch the distribution of direct stress in

the beam cross$-$section.

Answer: At $1,0\mathrm{.}92\frac{M_x}{h^2}$; at $2,-0\mathrm{.}65\frac{M_x}{h^2}$; at $3,0\mathrm{.}65\frac{M_x}{t}{h}^2$ at $4,-0\mathrm{.}135\frac{M_x}{t^2}$