Hybrid Oriented Strand Boards made from Moso bamboo (Phyllostachys pubescens Mazel) and Aspen (Populus tremuloides Michx.): uniformly mixed single layer uni-directional boards

This study is first in a series investigating the combination of Moso bamboo (Phyllostachys pubescens Mazel) and aspen (Populus tremuloides Michx.) to fabricate hybrid strand based panel composites. Here the wood and bamboo strands were evenly mixed together to form a thin, uni-directional strandboard 10 mm in thickness. The use of 30 % aspen strands was to improve the compaction and consolidation of the hard, uncompressible bamboo. The effects of replacing most of the aspen strands (70 %) with bamboo strands on board strength properties (IB, MOR, MOE) and moisture resistance were assessed. The effect of strands cut from the node free (internode) or node tissue portions of the culm on board properties was also systematically investigated. Substitution with 70 % internode Moso bamboo strands increased MOR by over 40 % compared with pure aspen and significantly lowered thickness swell and water absorption. Substituting aspen with the bamboo strands resulted in no change in MOE, in keeping with the tendency for natural Moso bamboo tissue to be high in bending strength and fracture toughness but lower in specific stiffness. The presence of node tissue in the bamboo strands significantly reduced the consolidation and mechanical properties of the composites.