Buckling of timber columns exposed to fire

• Published in: Fire safety journal 2011-10, Vol.46 (7), p.431-439
• Main Authors: Schnabl, S., Turk, G., Planinc, I.
• Format: Article
• Language: English
• Subjects: Applied sciences; Buckling; Building technical equipments; Buildings; Buildings. Public works; Charring; Columns (structural); Exact sciences and technology; Exposure; Fire; Fire behavior of materials and structures; Fire protection; Fires; Materials; Mathematical models; Moisture content; Reissner beam; Semi-analytical solutions; Strength of materials (elasticity, plasticity, buckling, etc.); Structural analysis. Stresses; Timber; Timber (structural); Wood
• ISSN: 0379-7112
• DOI: 10.1016/j.firesaf.2011.07.003

A mathematical model for structural behavior of timber columns under fire has been proposed. The semi-analytical study has been carried out for evaluating the load-carrying capacity of timber columns exposed to fire. Particular emphasis has been given to critical buckling loads. For this purpose, a parametric study has been performed by which the influence of slenderness ratio, load level, and water content on critical buckling loads of timber columns have been investigated. The results of this preliminary study showed that the present semi-analytical method is conservative compared to the two simplified calculation methods offered by Eurocode 5 if the transfer of water is neglected, while, on the other hand, the results agree well for a water content of 12%. Moreover, for higher water contents, the present semi-analytical model is non-conservative compared to the Eurocode 5 methods. ► Buckling loads of timber columns under fire have been calculated. ► The influence of water content on buckling loads has also been investigated. ► The results are conservative compared to Eurocode 5 if water transfer is neglected. ► On the other hand, the results agree well for a water content of 12%. ► Moreover, for higher water contents, the present method is non-conservative.