(a) Briefly explain why the Tresca yield criterion will result in a more conservative (safer) design than that based on von Mises criterion. (b) A cast alloy structure, ABCD is bolted at its base, A...

(a) Briefly explain why the Tresca yield criterion will result in a more conservative (safer)
design than that based on von Mises criterion.
(b) A cast alloy structure, ABCD is bolted at its base, A and carries a load of 235 N at end D, as
shown in Figure Q1. The diameter of the structure is 20 mm. Take the yield strength of the
alloy at 70 MPa:
(i) Determine the stress acting in the material of the structure at point B. Draw the stress
element and indicate the stress values.
(ii) Determine if this stress state would cause yielding of the material by calculating the factor
of safety using both the Tresca and von Mises yield criterion.
(iii) Draw the loci of both yield criteria in the principal stress axes and indicate the stress state
of part (ii) on the plot.