고체역학 (Gere) — Axially Loaded Members: Problem 2.5-16

2.5-16 A rigid bar $ABCD$ is pinned at end $A$ and supported by two cables at points $B$ and $C$ (see figure). The cable at $B$ has a nominal diameter $d_B = 12\text{ mm}$ and the cable at $C$ has a nominal diameter $d_C = 20\text{ mm}$. A load $P$ acts at end $D$ of the bar. What is the allowable load $P$ if the temperature rises by $60^\circ\text{C}$ and each cable is required to have a factor of safety of at least 5 against its ultimate load? Note: The cables have an effective modulus of elasticity $E = 140\text{ GPa}$ and coefficient of thermal expansion $\alpha = 12 \times 10^{-6}/^\circ\text{C}$. Other properties of the cables can be found in Table 2-1, Section 2.2.