State of Structural Timber Fire Endurance
Keywords:Fire endurance, fire resistance, timber, wood, columns, beams, walls, floors, panels, thermal properties, strength, wood assemblies, wood components
AbstractThe paper is motivated by the need for information relating to the design and behavior of wood structural components. Such information is critically reviewed. Most standard conventional components have been five tested under the sponsorship of materials suppliers or designers. However, only the fire endurance of floors and columns have both models and experimental evidence available for use. Models for the fire endurance of heavy timber, or glulam, beams are presented that are based on reduction of the cross section with duration of fire exposure and a reduction of strength of the outer fibers. Essentially no experimental information is available on model effectiveness. No models for the performance of wood-base wall systems were found, but extensive experimental ratings exist. To facilitate further research, a review of the influence of fire on wood and wood properties is given. Included are strength and deformation under load, charring of solid sections and panels, temperature distribution, and thermal properties. Research needs, in addition to filling the gaps found, include: analysis of risk based upon both variability of the "fire load" and "structural fire resistance"; and benefit/cost analyses on fire protection.
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