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

Abstract

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.

Hybrid oriented strand boards made from Moso bamboo (Phyllostachys pubescens Mazel) and Aspen (Populus tremuloides Michx.): species-separated three-layer boards

“…node/internode for IB in the hybrid and pure Moso boards the average of node and internode boards within each board type was plotted. Findings encountered in the mixed hybrid boards (Semple et al 2015a), i.e. board quality problems resulting from nodes in strands, and the beneficial effects of bamboo strands on dimensional stability of boards were discussed comprehensively and therefore not repeated here.…”

“…The procurement, breakdown and re-saturation of Moso bamboo culm pieces for stranding, and the strand production methodology were covered in Semple et al (2015a). Aspen strands were mill strands of the face and core furnish used to make industrial OSB, supplied separately by Weyerhauser, Edson, AB.…”

“…OSB strength properties decrease linearly with increasing fines content therefore the fines should be confined only to the core of the board (Barnes 2002). The methodology used to apply resin to the strands and hot press the mats was described in Semple et al (2015a), only this time a three layer mat was assembled by using the orienter to align the top and bottom layers of strands (50 % of total furnish weight), but removing the orienter and randomly distributing the middle core layer. For comparative purposes all the boards including aspen controls were pressed to a common thickness of 11.1 mm (7/16th inch) and a target density of 752.9 kg/m 3 (47 pcf).…”

“…Compared with most of the conventional bamboo panel products currently in production, the OSB process represents one of the best opportunities for automation, property control and consistency, mass production, and resin efficiency in manufacture of bamboo-based building materials, with minimal waste. A general introduction to Moso bamboo, its current processing industries and their shortcomings was given in Semple et al (2015a). In that study Moso bamboo strands were evenly mixed with 30 % aspen strands to form single layer uni-directionally oriented strand boards.…”

Multiscale Modelling of Moso Bamboo Oriented Strand Board

“…These inputs are shown in Table 1. (Semple et al 2015d), 3 (Malekmohammadi et al 2015), 4 (Semple et al 2015a) The densities of the sublayers from the VDPs, PF resin weight fraction of 6% (Semple et al 2015c, d), and assumed resin density of 1400 kg/m 3 (Malekmohammadi et al 2015) are used to calculate resin volume fractions in each layer. Void volume fraction is then calculated similarly, with a parent material density of 745 kg/m 3 (Semple et al 2015c) and assuming no densification in the core (minimum density layer in middle region of the board depth).…”