고체역학 (Gere) — Torsion: Problem 3.4-5

3.4-5 A hollow tube ABCDE constructed of monel metal is subjected to five torques acting in the directions shown in the figure. The magnitudes of the torques are \(T_1 = 100 \text{ N}\cdot\text{m}\), \(T_2 = T_4 = 50 \text{ N}\cdot\text{m}\), and \(T_3 = T_5 = 80 \text{ N}\cdot\text{m}\). The tube has an outside diameter of \(d_2 = 25 \text{ mm}\). The allowable shear stress is \(80 \text{ MPa}\) and the allowable rate of twist is \(6^\circ/\text{m}\). Determine the maximum permissible inside diameter \(d_1\) of the tube.