Yielding, stängd tub

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A long circular steel tube having a mean diameter of 254 mm and 3.2 mm wall thickness is subjected to an internal pressure of 4.83 MPa. The ends of the tube are closed. The yield stress of the steel is 227 MPa. Find the additional axial tensile load F which is needed to cause yielding of the tube, based on the von Mises criterion and Tresca criterion, respectively.

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