Distortional-Global Interaction in Cold-Formed Steel Lipped Channel Columns: Buckling Analysis, Structural Behavior and Strength

03/19/2020

The goal of the present research is the distortional-global (D-G) buckling interaction of cold-formed steel (CFS) lipped channel (LC) columns, in its buckling, structural behavior and strength nature. Some studies on this topic have been conducted in the literature, however, the D-G interaction is not well known and needs more attention. For an elastic buckling analysis, a software entitled FStr Computer Application Program is developed. The application is based on the Finite Strip Method, mainly focused in a simple and accessible interface. The FStr program generates the modal shapes and insert as initial geometric imperfections in the finite element software ANSYS, in order to perform a geometric and material nonlinear analysis. Both, the FStr program and the finite element model are validated with available numerical examples and laboratory tests from the literature. Moreover, for the structural behavior and column strength, it is carried out stability paths from previous nonlinear analysis, for different combination of initial geometric imperfection of global and distortional modes. The buckling mode combination as initial geometric imperfection helps to understand the D-G buckling interaction, which is difficult to predict with a simple elastic buckling analysis. The results of the initial imperfection combination have shown that, for high yielding steel, the global initial geometric imperfection provides the most detrimental ultimate load. Additionally, a parametric study varying the column’s length have shown that the nominal axial strength for global buckling equation, already in the standards, is enough to cover the DG coupled phenomenon.

Autores da comunidade :

• 

  J

  João Alfredo de Lazzari

  ist428971

Master of Science, in Civil Engineering

civil-engineering - Engenharia Civil

Palavras-chave

• Distortional-global buckling interaction
• Coldformed steel columns
• FSM elastic buckling analysis
• FEM numerical non-linear analysis

eng - Inglês

Entidade financiadora da bolsa/projeto

CNPq

Nome da bolsa/projeto: Bolsa de Mestrado do CNPq

Fonte de financiamento: Conselho Nacional de Desenvolvimento Científico e Tecnológico

Número de bolsa/projeto: 131199/2018-8

Entidade financiadora da bolsa/projeto

FAPERJ

Nome da bolsa/projeto: PROGRAMA BOLSA NOTA 10 – CATEGORIA MESTRADO NOTA 10

Fonte de financiamento: Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro

Número de bolsa/projeto: E-26/200.825/2019 (242580)