A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Numerical modelling of cold-formed steel built-up columns
Abstract Built-up cold-formed steel structural members can provide technically and economically advantageous solutions in cold-formed steel construction. However, there is a need for a deeper understanding of their stability behaviour, and this paper demonstrates that detailed, accurate and reliable finite element models provide an excellent means to achieve this. Apart from the typical issues to be considered in the high-fidelity modelling of thin-walled members, which include geometric and material nonlinearity, element type, mesh density, and the modelling of imperfections and boundary conditions, the paper focuses on two additional complications which arise in built-up members: the modelling of connectors, and contact between constituent parts. A number of alternative techniques to model connector behaviour are investigated and their effect on the predictions of the ultimate capacity quantified by benchmarking against experimental data. Various successful strategies to mitigate stubborn convergence problems, which almost inevitable originate when modelling complex contact problems, are also presented. It is demonstrated, however, that the inclusion of contact as a model feature does not have a significant effect on the predicted capacity in the majority of the considered cases, with its influence typically remaining limited below 10%. The validated models were further used in parametric studies which showed that once the connector spacing is short enough to prevent global instabilities of the component sections between connector points, its effect on the ultimate capacity of the built-up column is very small within the practical range of connector spacings. Modelling connector lines as continuous longitudinal constraints tying surfaces together, on the other hand, is bound to significantly overestimate the capacity.
Highlights Convergence issues can be overcome by Adding artificial damping and modifying solution control parameters. Modelling connectors with PLANAR elements and assigning them the load-slip behaviour leads to best results. Effect of connector spacing becomes noticeable when shorter than the local buckling half-wavelength. Contact between the components only has a modest effect on the ultimate capacity.
Numerical modelling of cold-formed steel built-up columns
Abstract Built-up cold-formed steel structural members can provide technically and economically advantageous solutions in cold-formed steel construction. However, there is a need for a deeper understanding of their stability behaviour, and this paper demonstrates that detailed, accurate and reliable finite element models provide an excellent means to achieve this. Apart from the typical issues to be considered in the high-fidelity modelling of thin-walled members, which include geometric and material nonlinearity, element type, mesh density, and the modelling of imperfections and boundary conditions, the paper focuses on two additional complications which arise in built-up members: the modelling of connectors, and contact between constituent parts. A number of alternative techniques to model connector behaviour are investigated and their effect on the predictions of the ultimate capacity quantified by benchmarking against experimental data. Various successful strategies to mitigate stubborn convergence problems, which almost inevitable originate when modelling complex contact problems, are also presented. It is demonstrated, however, that the inclusion of contact as a model feature does not have a significant effect on the predicted capacity in the majority of the considered cases, with its influence typically remaining limited below 10%. The validated models were further used in parametric studies which showed that once the connector spacing is short enough to prevent global instabilities of the component sections between connector points, its effect on the ultimate capacity of the built-up column is very small within the practical range of connector spacings. Modelling connector lines as continuous longitudinal constraints tying surfaces together, on the other hand, is bound to significantly overestimate the capacity.
Highlights Convergence issues can be overcome by Adding artificial damping and modifying solution control parameters. Modelling connectors with PLANAR elements and assigning them the load-slip behaviour leads to best results. Effect of connector spacing becomes noticeable when shorter than the local buckling half-wavelength. Contact between the components only has a modest effect on the ultimate capacity.
Numerical modelling of cold-formed steel built-up columns
Meza, Francisco J. (author) / Becque, Jurgen (author)
Thin-Walled Structures ; 188
2023-04-12
Article (Journal)
Electronic Resource
English
Experimental study of cold-formed steel built-up columns
| Elsevier | 2019
Closed built‐up cold‐formed steel columns under compression
| Wiley | 2023
Closed built‐up cold‐formed steel columns under compression
| Wiley | 2023