Bending of stiffened plates considering different stiffeners orientations

Structural mechanics

In engineering, the search for geometric configurations that lead to superior performance is always a design goal. Regarding structural components, such as plates, it is necessary to guarantee limits for its deflections, according to design standards. In this sense, methodologies devoted to reducing the out-of-plane displacements by geometric analysis are a relevant to subject research. Therefore, the present work is addressed to study several arrangements of stiffened steel plates defined by the Constructal Design Method (CDM). These plates were analyzed and solved applying computational modeling based on the Finite Element Method (FEM), aiming through the Exhaustive Search (ES) technique to evaluate the influence of stiffeners orientation on to the maximum deflection. Taking a non-stiffened plate as reference and keeping the total material volume constant, portions of its volume were transformed into stiffeners through the volumetric fraction parameter, representing the ratio between the volumes of stiffeners and reference plate. Adopting volumetric fraction values of 0.1; 0.2; 0.3; 0.4 and 0.5, it were established for each one 25 geometric arrangements of stiffened plates, considering the stiffeners orientations in 0 ° and 45 °, varying for each new arrangement the ratio between the height and thickness of the stiffeners hs/ts. The results showed that transforming a portion of material from a non-stiffened plate into stiffeners can decrease the maximum deflections by more than 95 %. Besides that, it has been demonstrated that stiffeners oriented at 45 ° can reduce maximum deflection by more than 60 % compared to stiffeners traditionally oriented at 0 °.