Bamboo is the fastest-growing plant globally and is known for its strength and resilience, but why is bamboo so strong? The foundation of bamboo’s high strength-to-weight ratio can be attributed to the unique properties stemming from the natural structure of its fibers.
Bamboo consists of an epidermis, vascular bundles, and parenchyma cells, all embedded by supporting fibers. These fibers consist of cellulose microfibrils intertwined with hemicellulose and lignin called lignin-carbohydrate complex (LCC), thus enabling bamboo to be a structurally robust plant.
Bamboo’s strength is a significant part of its ever-growing popularity, and it can also bend without breaking. It is fast becoming a great advantage to many industries due to its tensile strength and durability. Let’s explore the reasons why bamboo is so strong as well as some of the qualities of bamboo pertaining to its strength.
What Makes Bamboo So Strong?
Bamboo is incredibly strong and naturally stronger than many other processed materials used worldwide in construction nowadays. Due to its strength, it features several areas of expertise, such as construction. It is gaining increasing interest in items such as cooking utensils, and bamboo is also being acquired for medicinal reasons.
Bamboo fibers are structurally long and thin, run the length of the plant, and are what, in essence, give the plant its renowned sturdiness. The chemical composition of bamboo fibers is where the secret of its strength lies.
“Bamboo has hundreds of fibers surrounded by lignin matrix that bind the fibers together, “said Dr. Alireza Javadian, a co-author of many studies on bamboo’s potential for construction purposes. “These fibers are a major point of load transfer that provides its strength.”
Bamboo comprises three major compositions, namely:
- Cellulose
- Hemicelluloses
- Lignin
These chemical compositions supply around 90% of the total mass of the bamboo. The minor constituents of bamboo would be:
- Protein
- Tannins
- Fat
- Pectin
- Pigments
- Ash
Other components would also include waxes, resins, and inorganic salts. The chemical composition of bamboo fiber can be broken down into percentages and depicted as follows:
|
CHEMICAL COMPONENTS |
PERCENTAGE |
|
Pectin |
0.37% |
|
Aqueous Extract |
3.16% |
|
Lignin |
10.15% |
|
Hemicellulose |
12.49% |
|
Cellulose |
73.83 % |
The chemical composition of wood and bamboo is similar. Still, wood has a lower content of minor constituents than bamboo.
Additional Qualities Adding To Bamboo’s Strength
Bamboo has many more additional properties that complement its strength capabilities:
Flexibility
Since the bamboo fibers run along its length, they act as natural hinges enabling them to bend and flex without breaking. This makes bamboo ideal for areas prone to earthquakes and high winds due to the flexible structure allowing the action of bending to occur without causing breakage.
In Costa Rica in 1991, a group of bamboo houses managed to withstand an earthquake of 7.6 on the Richter scale, while the concrete and wood houses suffered considerable damage.
The ability for bamboo to not break when being forced to bend gives it an upper hand against many other materials.
Tensile Strength And Compression
Tensile strength is the resistance offered by an object to break under tension. The fibers in bamboo are tightly interwoven, resulting in a very high tensile strength, thus providing exceptional resistance to tension. Compared to steel, bamboo has a much higher tensile strength.
This makes bamboo impressively strong, which is why many people often say bamboo is stronger than steel. Steel has a tensile strength of 23 000 pounds per square inch, whereas bamboo has a notable tensile strength of 28 000 pounds.
Bamboo is more robust than steel because its molecular structure is more firmly packed. However, the tensile strength of bamboo varies according to species and specific plant age.
As for compression, bamboo has a very high compression strength. This means that bamboo can withstand a substantial amount of weight being forced down on it.
Moisture Resistance
Unlike most types of wood, treated bamboo is less prone to swelling when exposed to moist conditions as it boasts natural moisture-resistant properties. Therefore, adequately treated bamboo is an excellent material for manufacturing outdoor furniture, particularly those to be enjoyed in moist, humid weather conditions.
Hardness and Density
Bamboo is ideal for use in high-traffic zones such as floors, as it is harder than most woods, enabling resistance to general everyday wear, tear, and denting. Bamboo is also relatively dense despite it being a naturally hollow grass.
Lightweight
Bamboo is easy to lift, maneuver and transport because it is lightweight. It may be light, but its strength remains intact.
Sustainability
Bamboo grows incredibly quickly, with some species reaching maturity in just a few years. Bamboo is also able to regenerate from its root system. This swift growth and renewability is why bamboo is considered to be a hugely sustainable and eco-friendly material.
Comparing The Strength Of Bamboo With Other Materials
Approximately 1600 known bamboo species worldwide are primarily known for their strength. Their relative strength varies from species to species, depending on their hardness, density, tensile strength, and compression.
Bamboo Vs. Wood
Bamboo is a perennial woody grass. However, when comparing it to other woods, it is more robust. That is, the tensile strength is stronger. Bamboo can be an eco-friendly answer when seeking alternatives to wood-based products as it takes approximately three years to mature compared to trees (timber), which take much longer.
The bamboo sector has undoubtedly gained a good boost as there is a demand for replacing traditional tree-based fibers.
Bamboo In Construction
Bamboo is regularly used in construction as its tensile strength is stronger than mixtures of steel and concrete. It is common to find bamboo used for reinforcement structures in construction, such as scaffoldings, etc.
Bamboo Vs. Plastic
Many products are being manufactured, prioritizing bamboo over plastic. The main reason for seeking bamboo as a plastic alternative is not only for its strength but also for its many environmental attributes.
The Strongest Bamboo In The World
Guadua Bamboo (native to South America) is considered the world’s strongest and most economical bamboo. It is used in all sorts of building and construction applications worldwide. Guadua Bamboo has the physical ability to withstand extreme weather conditions.
The Weaknesses Of Bamboo
Along with the impressive strength and excellent physical qualities of bamboo, the robust grass does, in fact, have a few weak points. Bamboo, in its natural state, can swell and rot if left untreated when exposed to moisture, water, or humid conditions.
Exposure to these types of conditions would attract decay, causing fungi and insects. Untreated bamboo will not last longer than a few years, and shrinkage and poor long-term durability in its natural state are drawbacks of using natural bamboo in structures.
Conclusion
The very dense fibers in bamboo give the grass its extreme strength and flexibility. These internal fibers work together to strengthen the bamboo, making the grass incredibly durable and able to withstand considerable weight. Resilient, durable, sustainable bamboo has the potential to become the ideal replacement for more traditional building and construction reinforcements.