고체역학 (Beer) — Principal Stresses Under a Given Loading: Problem 8.8

8.7 and 8.8 (a) Knowing that \(\sigma_{\text{all}} = 24\text{ ksi}\) and \(\tau_{\text{all}} = 14.5\text{ ksi}\), select the most economical wide-flange shape that should be used to support the loading shown. (b) Determine the values to be expected for \(\sigma_m, \tau_m\), and the principal stress \(\sigma_{\max}\) at the junction of a flange and the web of the selected beam. Loading for 8.8 (Fig. P8.8): A beam \(AF\) has overhangs. - Concentrated downward loads of \(20\text{ kips}\) at \(A\) and \(F\). - Support triangles at \(B\) and \(E\). - Uniformly distributed load of \(11\text{ kips/ft}\) between \(C\) and \(D\). - Distances: \(AB = 2\text{ ft}\), \(BC = 2\text{ ft}\), \(CD = 6\text{ ft}\), \(DE = 2\text{ ft}\), \(EF = 2\text{ ft}\).