Numerical Study of the Section Moment Capacity of Complex-Shaped Aluminum Mullions
Publication: Journal of Architectural Engineering
Volume 26, Issue 4
Abstract
Curtain wall systems made of an aluminum frame and infilled with glass panes are extensively used in present day high-rise buildings. The vertical members of the aluminum frame, known as mullions, are complex-shaped and are primarily subjected to bending action when the curtain wall panels are exposed to wind pressure or suction loading. This paper investigates the section moment capacity of 6063-T6 aluminum alloy mullion sections subjected to wind actions using a numerical study. An experimental study conducted to determine the section moment capacity of the mullions is summarized in this paper. The results from an experimental study on the mechanical properties of 6063-T6 aluminum alloy mullions are then presented including a suitable stress–strain model. Finite element models were developed to determine the section moment capacities of tested mullion sections, and the details of the finite element modeling procedure and the results are presented in this paper. The developed models included mullions used in the structural and captive glazing systems subjected to both wind pressure and suction loading and were validated using the available test results. Finite element analysis (FEA) results were compared with the predictions from three design methods, the limiting stress method (LSM), the direct strength method (DSM), and the total moment capacity approach (TMCA), based on which the most suitable design method is recommended.
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Acknowledgments
The authors would like to thank QUT for providing all the necessary support with testing and computing facilities, G. James Glass and Aluminium for providing the specimens and their engineers for the technical support, and Australian Research Council for providing the financial support to conduct this research project.
Notation
The following symbols are used in this paper:
- C
- damping matrix;
- E
- modulus of elasticity;
- F
- applied external force matrix;
- fe
- conventional limit of elasticity;
- fmax
- characteristic value of ultimate tensile strength;
- fx
- second reference stress;
- f0.1
- proof strength employing 0.1% offset method;
- f0.2
- proof strength employing 0.2% offset method;
- K
- global stiffness matrix;
- M
- mass matrix;
- n
- strain hardening exponent;
- U
- nodal displacement;
- nodal velocity;
- nodal acceleration;
- ɛ
- strain corresponding to the stress σ;
- ɛmax
- strain corresponding to the stress fmax;
- ɛo,e
- residual strain corresponding to the stress fe;
- ɛo,max
- residual strain corresponding to the stress fmax;
- ɛo,x
- residual strain corresponding to the stress fx;
- ɛu
- ultimate strain at fracture; and
- σ
- stress.
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Information & Authors
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Published In
Journal of Architectural Engineering
Volume 26 • Issue 4 • December 2020
Copyright
© 2020 American Society of Civil Engineers.
History
Received: Apr 27, 2018
Accepted: Apr 30, 2020
Published online: Jul 24, 2020
Published in print: Dec 1, 2020
Discussion open until: Dec 24, 2020
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