Mechanical Properties of Bamboo Plywood

Bamboo is a fast-growing, strong plant with high flexibility.

Bamboo plywood is an alternative building material used instead of conventional-wood plywood. This material is becoming more popular in "green" construction due to bamboo's fast growth rate and low environmental impact. Bamboo plywood is also popular in Asia and other areas where bamboo is readily available. This material has similar mechanical properties to those of wood plywood, but there are some differences.

Reduced Water Absorption

Bamboo-based plywood absorbs water less readily than conventional-wood plywood. This means that bamboo plywood sheets may contain less glue than wooden sheets, and that they are less likely to absorb significant water in damp conditions. Bamboo plywood can still be damaged by moisture, however, and should be stored in a dry area or under plastic sheeting. The wetter the bamboo is, the less strong and flexible it becomes.

Strength

Bamboo has a higher ability to resist breakage under load when compared to wood-based plywood. However, according to the European Journal of Wood and Wood Products, bamboo plywood has a lower internal strength than wood-based boards. Overall, bamboo plywood is stronger when it contains a higher percentage of glue or resin. When bamboo plywood breaks, it tends to be along the glue lines.

Flexibility

Bamboo plywood is a very flexible material. In fact, adding bamboo material to wooden plywood increases flexibility significantly. Bamboo-based sheets tend to be more easily bent without breaking than wood-based plywood sheets, and are appropriate for forming curves and organic shapes. Higher-glue sheets tend to be stronger when bent than sheets with low glue percentages. Bamboo bends more effectively when wet, but is also more fragile.

Considerations

The strength of bamboo plywood depends considerably on the type and construction of the building material. Oriented strandboard tends to be stronger than random strandboard, due to the organized nature of its construction. Bamboo plywood with a woven texture is still stronger. Likewise, bamboo plywood made using primarily material from the inside of the plant contains less silica and tends to absorb glue better, producing a board that's less likely to fall apart under stress.

References

• "Forest Products Journal"; Effect of Moisture Content and Density on the Mechanical Properties of Veneer-Bamboo Zephyr Composites; Jeang-Kwan Roh et. al.; March, 2009
• " Challenges for Science and Engineering in the 21 st Century"; How Does It Work, Bamboo-Based Waferboard; Hong-Jian Zhang; June 2000
• "Modern Bamboo Structures"; Status and Future of the Wood-Bamboo Composite Panel Industry in China; H. Q. Ren et. al.; 2008
• "Journal of Wood Science"; Effect of Board Density and Layer Structure on the Mechanical Properties of Bamboo Oriented Strandboard; Ihak Sumardi et. al.; December 2007
• "European Journal of Wood and Wood Products"; Physical and Mechanical Properties of Oriented Strand Lumber Made from an Asian Bamboo; Pannipa Malanit et. al.; February 2011