Don’t use bamboo to hold concrete - IET-GH advises builders

The Institution of Engineering and Technology, Ghana (IET-GH) has cautioned against using bamboo as reinforcement material instead of steel to hold concrete during construction in the country.

It said in the absence of established treatments and standards by the Ghana Standard Authority and Engineering Council, the use of untreated bamboo was not encouraged since it was not safe to do so.

The President of IET-GH, Henry Kwadwo Boateng, told the Daily Graphic that the institution had taken note of the increasing interest in the use of bamboo as a reinforcement material in concrete, circulating across various social media channels nationwide.

Additionally, he said some clients had adopted the material in construction, mistakenly believing it had been endorsed without seeking expert guidance.

Clarity

Mr Boateng said it was important to clarify that the IET-GH, particularly its civil engineering division, recognised the potential benefits of bamboo in its raw state as a laminate and composite material.

However, he said the use of bamboo as a direct replacement for steel reinforcement in concrete required careful consideration and further research.

“Bamboo is a natural composite polymeric material composed of a lignin matrix with fibrous elements, which are naturally bound together as an organic composite. However, bamboo is a carbon-based material from the grass family and if not adequately treated, it can decompose over time, particularly in alkaline or acidic environments,” he said.

He said the use of bamboo presented several advantages including economic benefits and that bamboo, for instance, created employment opportunities through farming, cultivation, processing and marketing.

Its production, Mr Boateng said could contribute to the country’s gross domestic product and that in addition to that, bamboo had environmental benefits including the absorption of carbon dioxide from the atmosphere and release of oxygen, contributing to a sustainable ecosystem.

System

He said its root system helped to prevent soil erosion and mitigate environmental degradation.

Additionally, he said substituting steel with bamboo in construction could reduce carbon emissions generated during steel manufacturing.

The IET-GH president said bamboo was more affordable than steel, readily available locally, and easy to access, making it a cost-effective alternative.

“While bamboo does not match the tensile strength of steel, it possesses a high tensile strength and an excellent strength-to-weight ratio. Historically, bamboo has been used in construction for centuries, including in traditional composite structures such as mud walls and “Atakpame” buildings.

“However, its use as reinforcement in concrete is a more recent development,” he said.

He said the IET-GH acknowledged the historical use of bamboo in mud buildings but emphasized that the conditions in concrete, particularly its alkaline environment, differed significantly from those in traditional mud construction methods.

Mr Boateng said bamboo tended to absorb water when mixed with fresh concrete, which caused swelling and that the “bamboo shrinks as it dries, which may leave spaces between it and the surrounding concrete, weakening the bond between them. 

Compromise

This can compromise the structural integrity of bamboo-reinforced concrete. To use bamboo as reinforcement material in concrete, he said further research was needed to address the long-term behaviour of bamboo as a natural polymeric material within a concrete composite.

Again, he said “effective treatment methods for bamboo are needed to minimise water absorption and improve bonding between the bamboo and the concrete matrix.”