고체역학 (Beer) — Pure Bending: Problem 4.124

4.124 A short length of a rolled-steel column supports a rigid plate on which two loads P and Q are applied as shown. The strains at two points A and B on the centerline of the outer faces of the flanges have been measured and found to be \(\epsilon_A = -400 \times 10^{-6} \text{ in./in.}\) and \(\epsilon_B = -300 \times 10^{-6} \text{ in./in.}\) Knowing that \(E = 29 \times 10^6 \text{ psi}\), determine the magnitude of each load. [Data from figure: \(A = 10.0 \text{ in}^2\), \(I_z = 273 \text{ in}^4\), Flange width \(b_f = 10 \text{ in.}\), Load eccentricities in \(z\)-direction = \(6 \text{ in.}\) and \(-6 \text{ in.}\)]