Stability analysis of advanced composite grid stiffened cylindrical shell

In accordance with the refined triangular Mindlin plate elements, a new triangular composite stiffened flat shell element is proposed to analyze the stability behavior of advanced composite grid stiffened cylindrical shell (AGS). Displacement compatibility between the stiffeners and plate is well maintained by using the same shape functions for both elements, and additional degrees of rotations of the stiffeners are introduced. In addition, the number and orientation of the stiffeners in the element can be defined by users, thus the meshing procedure is rather convenient. The numerical results testify its effectiveness, especially, for analyzing the case of the plate stiffened by thick beams. The effects of stiffened style, such as inner-stiffened and outer-stiffened shell upon the buckling loads of AGS, are also carried out.