Dimensionamento de colunas em perfis U pultrudados reforçados com fibra de vidro sob falha global

Abstract

The several advantages of glass fiber reinforced polymers (GFRP), in regards to structural efficiency, durability in aggressive environments, diversity of crosssections, lightness, high strength, easy and quick installation, among others, have stimulated the use of this constructive system in different sectors of civil construction. In this context, the current work presents, through a numerical-computational study, the proposition of a rational/direct methodology for the design of fixed-ended columns consisting of U profiles formed from GFRP under global failure mode by flexuraltorsional or flexural. The first step consists of the careful selection of columns (geometry and lengths) to be evaluated, using the GBTul program (according to the Generalized Beam Theory). After that, the FEM (Finite Element Method) is applied via ANSYS computational/commercial code for non-linear physical and geometric analysis, using shell finite elements, to simulate the structural behavior of buckling, postbuckling and ultimate strength. The difference in behavior between profiles with flexural buckling and flexural-torsional profiles after buckling is evident. The results obtained, namely equilibrium trajectories, buckling modes and the resistance defined by a collapse criterion, are used to evaluate modifications in the current resistance curves of the Direct Strength Method, currently exclusive to thin-walled metallic elements.