Fire Design of Timber Structures

Abstract

The aim of this master thesis was to do structural fire design calculations of timber constructions, using “the reduced/effective cross-section method” and “the reduced properties method” on a beam with cross section 240 mm × 700 mm, which is exposed to fire on three sides, and on a column with cross section 400 mm × 400 mm, which is exposed to fire on four sides. These calculations are done for the beam and for the column without and with corner rounding. In these calculations, it is checked design for normal conditions and for fire conditions both for the beam and for the column mentioned above without and with corner rounding. It is worked an example using “the North American charring rate method”,  without corner rounding to check whether the fire design is ok or it fails. Another example is also worked using “The parametric char rate method” to check whether the beam or the column can resist a burnout of the room. The methods are all based on the same concepts, but the assumptions and details are different. The methods give different results depending on the beam and column geometry and different ratios of dead load to live load.