Accelerated weathering of nine tropical wood species from Cameroon
S Pankras, Jinzhen Cao, D P Kamdem
The natural durability of tropical species for building components has been a subject of recent concern and questioning, mainly the resistance to weathering. Weathering resistance of nine tropical species from Cameroon, namely Azobe, Bilinga, Bubinga, Teak, Dousie, Moabi, Musanga, Sipo and Padauk were evaluated using an accelerated weatherometer for 2016 hours. Measurement of moisture fluctuation, weight loss, color change, and surface texture were taken at regular intervals of time. It was found that the weight loss, surface roughness and color change increased with the exposure time of samples to accelerated weathering conditions as compared to the initial property at the beginning of the test. The amount of weight loss during the testing increases with the amount of moisture fluctuation in samples during the test. Moisture fluctuation in sample during weathering was related to the weight loss of weathered samples indicating that the moisture fluctuation may be an indicator of durability.
The lowest weight loss and water absorption were observed with Azobe, Padouk, Teak, Doussie and bilinga whereas highest weight loss were obtained for Moabi and Musinga. For color change, reddish, brownish, yellowish colored species such as padouk, Doussie, bilinga exhibit high values of color change parameter in comparison toMussanga light whitish colored species. .