Concrete (a >$100 billion dollar industry) is made by mixing cement, gravel and sand with water and various chemical and physical additives. A common industry problem is plastic shrinkage cracking, when differential shrinking occurs upon drying.
Currently, cracking in concrete is the most significant cause for concrete repair or replacement. Of the 500 million cubic yards of concrete used annually in Canada and the US, ~10% is used for repair/replacement of cracked concrete. Very little concrete contains plastic fibers (a conventional method of crack mitigation technology), as performance is lacking, while hemp fiber reinforcement, such as NForce-Fiber® performs significantly better at mitigating these cracks. As cracking is the primary reason of concrete failure, the addition of fiber reinforcement for crack mitigation will lead to significant reduction of concrete needing repair and replacement; a savings of 0.8 T of CO2e per cubic meter of concrete. Hemp fiber reinforcement could increase the longevity of 5,000,000 cubic meters of concrete annually, leading to increased energy efficiency in the concrete industry, and a reduction of annually-required concrete.
Reinforcing fiber for controlling plastic shrinkage cracking in concrete is a constantly growing trend, responding to an ever increasing demand for higher quality concrete infrastructure with longer life-span. Conventional synthetic fiber products, such as plastic and glass fibers, are often imported and produced from unsustainable and non-renewable feedstock, which have limited performance due to poor bonding and dispersion in concrete.
NForce-Fiber®, the only hemp fiber reinforcement for concrete, is produced using sustainable, domestically-grown hemp, that is cost efficient and offers high performance. NForce-Fiber® has also been proven to be more resistant to elevated temperatures in comparison to most synthetic fibers. NForce-Fiber® has been technically developed, tested, verified and commercially implemented by world renowned experts in the concrete industry.
Why is hemp fiber a viable solution for concrete reinforcement?
- Hydrophilicity (love of wet environments), allows the fibers to disperse readily in the concrete mix and bond strongly with the concrete matrix.
- The fibers remain intact allowing them to reinforce the concrete matrix.
- Consistently-sized hemp fibers have a high probability of bridging crack gaps.
- Hemp fibers do not protrude from the concrete, making them easy to finish.
- Hemp fibers have significant environmental benefits when compared to conventional synthetic fibers.
From the sustainability and environmental impact perspectives, NForce-Fiber® concrete reinforcing fibers result in a technology with substantial benefit to the public including: Reduction of replaced concrete due to high-performance in crack mitigation, GHG emission reduction, energy conservation, natural resource conservation and replacement of synthetic products, and high embodied manufacturing energy and/or derived from non-renewable resources.
- Portland Cement Association. Green in Practice 102 - Concrete, Cement, and CO2 Technical Brief. http://www.concretethinker.com/technicalbrief/Concrete-Cement-CO2.aspx (accessed June 20, 2015).
- Chester, Mikhail V. (2008) Life-cycle Environmental Inventory of Passenger Transportation in the United States. Institute of Transportation Studies. University of California, Bekeley, USA. Retrieved from: http://escholarship.org/uc/item/7n29n303 (accessed June 20, 2015).