This study investigated the swelling behavior, rate of swelling and dimensional stability of nine tropical hardwood species from Cameroon, namely ayous (T. scleroxylon), bilinga (N. diderrichii), bubinga (G. tessmannii), iroko (C. excelsa), Makore (M. heckelii), moabi (B. toxisperma), movingui (D. benthamianus), teak (T. grandis) and zingana (M. brazzavillensis). Continuous swelling was monitored with water immersion time for 48 hours on small wood blocks using linear variable differential transformers (LVDTs). The amount of water absorbed by the wood was found to depend on the wood porosity. Among the reported woods, teak showed lowest swelling and taken as dimensionally stable wood for comparison. Ayous, iroko and movingui were relatively more dimensionally stable compared to bubinga, makore and moabi. Radial swelling rate was much higher than tangential. Bubinga, bilinga and zingana showed higher radial swelling rates compared to iroko, teak and makore. Similarly, higher rates of tangential swelling were shown by bubinga and movingui compared to teak, makore and moabi. T/R ratio or anisotropy of different wood species was within the normal range. Linear relationship between total radial plus tangential swelling and wood density was weak.

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