고체역학 (Gere) — Applications of Plane Stress: Problem 8.3-5

8.3-5 An inflatable structure used by a traveling circus has the shape of a half-circular cylinder with closed ends (see figure). The fabric and plastic structure is inflated by a small blower and has a radius of 12 m when fully inflated. A longitudinal seam runs the entire length of the “ridge” of the structure. If the longitudinal seam along the ridge tears open when it is subjected to a tensile load of 100 N/mm of seam, what is the factor of safety \( n \) against tearing when the internal pressure is 3.5 kPa and the structure is fully inflated?