Abstract
In this Chapter, the analysis and design of cold-formed steel portal frames (CFS) are considered. A review of the literature of tests reported on cold-formed steel joints is first presented. The requirement in a beam idealisation of cold-formed steel portal frames to consider both the semi-rigidity and finite connection length is then shown through comparisons against full-scale test results. For the case of joints formed through the web, a reduced strength because of the bimoment in the section is demonstrated. A suit of design equations to predict the buckling resistance of various eaves and apex brackets was also presented. For practical small-sized frames, however, serviceability design is more important, to avoid tearing of the cladding at the gable end frames caused by load returned to the gables as a result of stressed skin action. The effect of stressed skin action, for portal frames having small spans, is then shown. For such frames, a 3D stressed-skin frame analysis should be used for design purposes. The performance of the CFS portal frames subject to seismic loading was also investigated showing stable cyclic hysteresis response, good energy dissipation capacity and ductility during loading. Finally, the performance in fire conditions is described, suggesting the potential advantages of fire protection to the side rails. It was also demonstrated that buckling of the members and not the failure of fasteners remains the main design consideration when analysing CFS structures subject to elevated temperatures.
Original language | English |
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Title of host publication | Recent Trends in Cold-Formed Steel Construction |
Editors | Cheng Yu |
Publisher | Woodhead Publishing Limited |
Chapter | 14 |
Pages | 387-483 |
Number of pages | 97 |
Edition | 2nd |
ISBN (Print) | 9780443190551 |
DOIs | |
Publication status | E-pub ahead of print - 19 Oct 2024 |