Abstract
The torispherical shell is a structure which is composed of a spherical, a toroidal and a cylindrical shell. When the internal pressure is loaded on a torispherical head, hoop compression stress occurs around the junction between the spherical and toroidal shell, and this hoop compression stress can cause buckling. For the evaluation of the buckling pressure by the FEM, it is important to give appropriate initial imperfection setting to the analysis model. The purpose of this study is to investigate the shape and the magnitude of the initial imperfection used for the torispherical head buckling analysis. The results show that the practical setting of initial imperfection obtained here indicates the same tendency of conventional experimental studies.