Cold-formed steel sections are commonly used in low-rise commercial and residential buildings.During fire events, cold-formed steel structural elements in these buildings can be exposed to elevatedtemperatures. Hence after such events there is a need to evaluate their residual strengths. However,only limited information is available in relation to the residual strength of fire exposed cold-formedsteel sections. This research is aimed at investigating the distortional buckling capacities of fireexposed cold-formed lipped channel sections. A series of compression tests of fire exposed, shortlipped channel columns made of varying steel grades and thicknesses was undertaken in this research.Test columns were first exposed to different elevated temperatures up to 800 oC, and then tested tofailure after cooling down. Suitable finite element models were developed with post-fire mechanicalproperties to simulate the behaviour of tested columns and were validated using test results. Theresidual compression capacities of short columns were also predicted using the current cold-formedsteel standards and compared with test and finite element analysis results. This comparison showedthat ambient temperature design rules for columns can be used to predict the residual compressioncapacities of fire exposed short or laterally restrained cold-formed steel columns provided themaximum temperature experienced by the column can be estimated after a fire event. Such residualcapacity assessments will allow engineers to evaluate the safety of fire exposed buildings. This paperpresents the details of this experimental study, finite element analyses and the results.
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