Gere & Goodno — Applications of Plane Stress: Problem 8.3-11

8.3-11 A standpipe in a water-supply system (see figure) is 3.8 m in diameter and 150 mm thick. Two horizontal pipes carry water out of the standpipe; each is 0.6 m in diameter and 25 mm thick. When the system is shut down and water fills the pipes but is not moving, the hoop stress at the bottom of the standpipe is 900 kPa. (a) What is the height h of the water in the standpipe? (b) If the bottoms of the pipes are at the same elevation as the bottom of the standpipe, what is the hoop stress in the pipes?