고체역학 (Gere) — Applications of Plane Stress: Problem 8.2-3

8.2-3 A large spherical tank (see figure) contains gas at a pressure of 3.5 MPa. The tank is 20 m in diameter and is constructed of high-strength steel having a yield stress in tension of 550 MPa. (a) Determine the required thickness of the wall of the tank if a factor of safety of 3.5 with respect to yielding is required. (b) If the tank wall thickness is 100 mm, what is the maximum permissible internal pressure?