Optimally shaped torispheres with respect to buckling and their sensitivity to axisymmetric imperfections

Abstract A discrete version of dynamic programming is used to optimise elastic-plastic externally pressurised torispheres. Step-wise redistribution of mass along the meridian is allowed with an arbitrary number of segments. The optimally shaped torispheres seem to be sensitive to initial axisymmetric geometrical imperfections to the same extent as spherical caps/hemispheres—unlike torispheres with uniform thickness. The full advantage of 15–50% increase in buckling pressure requires shape control to a considerable degree of accuracy.

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