The Limit Load Determination in a Spherical Shell with a Branch Pipe under Combined Loading

An applied procedure of the elastic-plastic analysis and the limit plastic load determination is given for a spherical shell with a branch pipe under combined loading. The numerical elastic-plastic analysis of structural connections of the intersecting spherical and cylindrical shells is performed using the finite-element method, theory of shells, and theory of plastic flow. The modified mixed variational statement and two-dimensional tetragonal elements with a special scheme of independent approximation of the displacement and deformation fields in an element are used for the finite-element analysis of intersecting shells. The applied procedure is implemented using the developed ad hoc software SAIS. A variant of combined loading of the connection by internal pressure and bending moment with their proportional growth is considered. A generalized curve of limit plastic loads is obtained for a particular model of hemispherical shell with a branch pipe.

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