고체역학 (Gere) — Stresses in Beams (Basic Topics): Problem 5.5-16

5.5-16 Determine the maximum bending stress $\sigma_{\max}$ (due to pure bending by a moment $M$) for a beam having a cross section in the form of a circular core (see figure). The circle has diameter $d$ and the angle $\beta = 60^\circ$. Hint: Use the formulas given in Appendix E, Cases 9 and 15.