Simulação numérica e design construtal aplicados à flambagem elásto-plástica biaxial de placas retangulares com perfurações retangulares

Abstract

The use of thin plates in engineering is increasingly common. For being an element of easy employability in the naval, aerospace, civil and offshore platforms industry. In much of their work regime, they are subjected to compressive loads, which makes them more exposed to the phenomenon of buckling, a structural instability that causes displacement outside their plane. Elastoplastic buckling occurs after elastic buckling, which is determined according to the critical load. This is because there is a reorganization of the membrane stresses, causing the plate to withstand higher loads. The presence of perforations makes it necessary to have knowledge about their interference in the behavior of the plates. This work analyzed elasto-plastic buckling for rectangular plates with rectangular holes that are under biaxial compression. The configurations to differentiate them were chosen according to the ratio between the hole and plate volumes, the volumetric fraction, with values of 5%, 10% and 15% in relation to the total volume of the plate. The Construtal Design was applied, after having proven efficacy in solid mechanics problems, combined with the Finite Element Method and the Exhaustive Search technique. Optimal geometry was found for the three volume fraction configurations. It was noted that the best general configuration occurred in the first volumetric fraction and presented a NUS Last Normalized Stress = 0.84375, and represented an increase of 13.85% in relation to the best configuration of the second volumetric fraction and an increase of 29.45 % in relation to the best configuration of the third volume fraction. Keywords: Plate Buckling; Elastoplastic Buckling; Constructal Design; Finite Elements Method; Numerical Simulation.