고체역학 (Gere) — Stresses in Beams (Advanced Topics): Problem 6.5-11

6.5-11 A steel post (\(E = 200 \text{ GPa}\)) having thickness \(t = 3 \text{ mm}\) and height \(L = 2 \text{ m}\) supports a stop sign (see figure). The stop sign post is subjected to a bending moment \(M\) having its vector at an angle \(\theta\) to the \(z\) axis. Determine the orientation of the neutral axis and calculate the maximum tensile stress \(\sigma_t\) and maximum compressive stress \(\sigma_c\) in the beam. Assume that \(\theta = 30^\circ\) and \(M = 350 \text{ N}\cdot\text{m}\). Use the following numerical properties for the post: \(A = 373 \text{ mm}^2, c_1 = 19.5 \text{ mm}, c_2 = 18.5 \text{ mm}, I_y = 1.868 \times 10^5 \text{ mm}^4, \text{ and } I_z = 0.67 \times 10^5 \text{ mm}^4\).