Production and Properties of Oriented Cement-bonded Boards from Sugi: Cryptomeria japonica D. Don

摘要

Extractives in sugi (Cryptomeria japonica) inhibit the curing of cement, and hence wood-cement composites manufactured from sugi invariably have poor mechanical properties. The aim of this study was to manufacture high strength wood-cement composites from sugi by making boards from sapwood, which contains less of the extractives that inhibit cement curing, using a cement setting accelerator and orientating strands in the boards to maximise strength properties. By adopting these strategies, high strength boards could be produced despite cement hydration tests that showed that sugi sapwood inhibited the curing of cement. Manipulation of surface:core ratio and, to a lesser extent, strand thickness can be used to modify mechanical properties in bending (MOR and MOE), but not internal bond strength.