An engineer wishes to determine the shearing strength of a certain epoxy cement. The problem is to devise a test specimen such that the joint is subject to pure shear. The joint shown in the figure, in which two bars are offset at an angle θ so as to keep the loading force F centroidal with the straight shanks, seems to accomplish this purpose. Using the contact area A and designating Ssu as the ultimate shearing strength, the engineer obtains

The engineers supervisor, in reviewing the test results, says the expression should be

Resolve the discrepancy. What is your position?

-tan ) cos 4 SiH