고체역학 (Gere) — Stresses in Beams (Basic Topics): Problem 5.5-4

5.5-4 A simply supported wood beam AB with a span length $L = 4\text{ m}$ carries a uniform load of intensity $q = 5.8\text{ kN/m}$ (see figure). (a) Calculate the maximum bending stress $\sigma_{\max}$ due to the load $q$ if the beam has a rectangular cross section with width $b = 140\text{ mm}$ and height $h = 240\text{ mm}$. (b) Repeat part (a) but use the trapezoidal distributed load shown in the figure part b.