Calculation and selection of the optimum parameters of elastoplastic shells with a circular hole under combination loading

Abstract

1. The maximum stresses calculated for specific loads for variant 1, with allowance for the plastic strains, are reduced by 54% (σϕmax,ξ=0.5) compared to the stresses determined by means of the linear solution for the same loads. The change in these stresses for loading variants 2 is 37% (σϕmax,ξ=0.5) and 68% (σ s max;ξ=0.5). 2. An optimum parameter corresponding to the lowest stress concentration factor was chosen on the basis of data from numerical experiments conducted with different values of the parameter Fk* (Fig. 2), certain initial values for other parameters, and a specified load. In our case, the optimum ring from the viewpoint of uniformity of the stress state over the shell cross section examined here is the variant for which Fk*≈0.54083·10−1 (Ik*≈0.24375·10−3), which corresponds to a ring of rectangular cross section with the dimensions 0.02×0.02 m2. 3. The method described above can be used to calculate the elastic and inelastic axisymmetric states of complex shell structures with stress concentrators.