고체역학 (Gere) — Stresses in Beams (Advanced Topics): Problem 6.10-13

6.10-13 A hollow box beam with height \(h = 300\text{ mm}\), inside height \(h_1 = 250\text{ mm}\), width \(b = 150\text{ mm}\), and inside width \(b_1 = 100\text{ mm}\) is shown in the figure. Assuming that the beam is constructed of steel with yield stress \(\sigma_Y = 250\text{ MPa}\), calculate the yield moment \(M_Y\), plastic moment \(M_p\), and shape factor \(f\).