The influence of ribs stiffness and shape imperfections on stability of a ribbed folded plate structure

The stability of a ribbed thin-walled folded plate structure with various ribs stiffness and geometrically imperfect shape has been considered, in addition to the static and dynamic external load. The stability problem has been solved by a numerical algorithm, which is based on the reduced basis method. This algorithm uses the finite difference technique for the numerical approximation of the geometrically non-linear equations of motion of the general theory of thin shells. The vectors of the reduced basis are generated automatically and are used as modes of displacement of the structure to reduce the finite difference model. The critical loads have been determined for structure with different stiffness of ribs. The influence of the shape imperfections of the structure on its static and dynamic stability also has been studied.