Zur Abbrandrate von Holz in Abhängigkeit der Rohdichte

International audienceIn this study, the velocity of combustion (charring rate) of wood in relation to the mass density was determined. Three material types: Balsa, undensified and densified spruce and compressed laminated wood with material densities ranging between 155 and 1340 kg/m were investigated. The specimens were exposed for 30 min in a furnace to the ISO 834-1 (Fire-resistance tests - elements of building construction - general requirements. Sept. 1999) Standard Fire. The experimental results show that the charring rate decreases exponentially with the increase in density. For densities above 800 kg/m the charring rate reaches a constant value and becomes independent of the density. The reason for the non-linear charring behavior is the thermal conductivity of wood which increases with the increase in density. At the same time the isolating performance of the char layer decreases