Computational study of strengthening effects of stiffeners on regular and arbitrarily stiffened plates

In this paper, strengthening effects of stiffeners on regular and arbitrarily stiffened plates are discussed in terms of the ultimate strength limit (USL) obtained through full nonlinear transient analysis. This study starts from the investigation of strengthening effects of regular stiffened plates which are subjected to uniaxial stress and then arbitrarily stiffened plates that are subjected to biaxial stress. The optimal height, number, and arrangement of the stiffener that provide the best strengthening effect are revealed and it is also found that the strengthening effects of an arbitrarily oriented stiffener (or oblique stiffener) can be decoupled to two perpendicular regular stiffeners which are located in appropriate positions. Nonlinear buckling analyses were performed on the arbitrarily stiffened plates with one and two arbitrarily oriented stiffeners to verify this finding. The outcome of this paper can be further extended and applied to develop simplified semi-analytical models for buckling strength analysis of constructional plates.