고체역학 (Beer) — Shearing Stresses in Beams: Problem 6.7

6.7 The column shown is fabricated by connecting two channel shapes and two plates, using bolts of $\frac{3}{4}$-in. diameter spaced longitudinally every 5 in. Determine the average shearing stress in the bolts caused by a shearing force of 30 kips parallel to the $y$ axis.