고체역학 (Gere) — Tension, Compression, and Shear: Problem 1.3-12

1.3-12 Repeat 1.3-10 but use the method of sections to find member forces in AB and DC. Reference from Problem 1.3-10: Find support reactions at A and B and then use the method of joints to find all member forces. Let $b = 3\text{ m}$ and $P = 80\text{ kN}$. From the figure for Problem 1.3-10: A plane truss with joints A, B, C, D. Pin support at A, roller support at B. Angles: $\theta_A = 60^\circ$, $\theta_B = 40^\circ$. Member AC has length $b = 3\text{ m}$. Joint D is the midpoint of member AC (indicated by $b/2$ and $b/2$). External loads: At joint C, a downward force $P$ and a rightward force $2P$. At joint D, a leftward force $2P$.