고체역학 (Beer) — Principal Stresses Under a Given Loading: Problem 8.7

8.7 and 8.8 (a) Knowing that \(\sigma_{all} = 24\text{ ksi}\) and \(\tau_{all} = 14.5\text{ ksi}\), 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. (Problem 8.7 refers to Fig. P8.7: A beam \(ABCD\) with overhangs. \(AB = 10\text{ ft}\), \(BC = 30\text{ ft}\), \(CD = 10\text{ ft}\). Concentrated loads of \(20\text{ kips}\) at \(A\) and \(D\). Uniform load \(w = 2\text{ kips/ft}\) between \(B\) and \(C\). Supports at \(B\) and \(C\).)