Question

31. Consider a crane hook with a rectangular cross-section of overall size of 4 in (width) x 0.75 in (thickness) at the critical section A-A. In addition, there is a through-thickness hole at the centre of the section of diameter ¼ inch as shown in the sketch. A load F 6000 lbf is applied to the hook as shown in the sketch. [a]. Determine the extreme fiber stresses (σο, at-r, and r-ro) at section A-A. In your analysis, neglect the effect of stress concentration from the hole. [b]. Comment on how the presence of the hole will affect the factor of safety. [c]. Specify the stress state (all stress components) at following points around the periphery of the hole; P (left), Q (right), R (top) and S (bottom). 3/4 in Dia. (hole) 6-in R 0.75 in 2-in R. Section A-A

Answer 1

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