EFFECT OF ACCELERATED AGING ON THE FIRE REACTION PERFORMANCE OF TWO TYPES OF MODIFIED WOOD

This study aims to evaluate the effects of degradation caused by exposure to atmospheric agents over time (weathering) simulated in an accelerated aging chamber, as well as the fire behaviour of two types of modified wood: thermo-treated and acetylated. The samples were exposed to accelerated aging cycles, which combined condensation, UV radiation, and spraying, for four weeks, following the protocols based on the UNE-EN 927-6:2019 standard. After the aging process, the colour variation was analysed, and the appearance of deformations and splitting was also observed. Flammability tests were also carried out to investigate the fire reaction behaviour of the samples as a function of exposure time in the accelerated aging chamber. The results showed progressive lightening and colour loss intensity in both types of modified wood after aging. However, the cracks appeared more noticeable in the thermotreated wood. Acetylated wood samples exhibited worse fire behaviour than thermotreated wood, especially before the aging procedure. The aging process improved the reaction to fire of all samples, especially its self-extinguishing ability.