- Author
-
Ranby, A.
- Title
- Barformaga hos brandutsatta tunnplatsreglar. [Fire Resistance Design of Thin Walled Steel Sections.]
- Coporate
- Swedish Institute of Steel Construction, Stockholm, Sweden
- Report
-
Report 188:4
1999
78 p.
- Keywords
-
steels
|
walls
|
structures
|
fire resistance
|
temperature
- Abstract
- ONLY ABSTRACT IN ENGLISH The report describes how the resistance of thin walled steel sections can be designed with respect to local buckling, flexural buckling and torsional-flexural buckling in the case of fire. Calculations have been done according to StBK-N5, Swedish Code for Light-Gauge Metal Structures and Eurocode 3, part 1-3. Equivalent calculations have then been done with computer FE analysis. Since the yield point and modulus of elasticity decrease with the temperature, the load bearing resistance decrease as well. In-plane and out-of-plane deformations increases with the temperature. The results shows that the resistance can be calculated with the same methods under both normal temperatures and temperatures in case of fire. Calculations of the ultimate load shows results fairly in agreement with numerical FEM analysis. The effects of a temperature gradient across the section and different kind of bracing have been studied as well. The yield strength and elastic modulus must be reduced with regard to the temperature. The conclusion is that the yield point can be taken as the conventional 0.2 percent off set value, as well as accepted empirical expressions can be used, when designing the load bearing resistance of thin walled steel sections in case of fire.