고체역학 (Beer) — Introduction—Concept of Stress: Problem 1.55

1.55 In the structure shown, an 8-mm-diameter pin is used at \(A\), and 12-mm-diameter pins are used at \(B\) and \(D\). Knowing that the ultimate shearing stress is 100 MPa at all connections and that the ultimate normal stress is 250 MPa in each of the two links joining \(B\) and \(D\), determine the allowable load \(P\) if an overall factor of safety of 3.0 is desired.