Stronger Than Steel? – Hemp Rebar Could Start an Eco-Friendly Movement in Building Materials

Source: Cannabis.net | Author: Joseph Billions | Sep 3, 2022

Researchers from Rensselaer Polytechnic Institute, Troy, New York, confirm that hemp rebar could be a suitable alternative to steel in cement construction. Dan Walczyk, director of the manufacturing innovation center and professor of mechanical engineering, and Alexandros Tsamis, associate director of the Architecture Science and Ecology Center and assistant professor of architecture at Rensselaer Polytechnic, say they have produced an alternative to steel in concrete buildings and various infrastructure projects. Both scientists agree that hemp-based natural fiber-reinforced thermoplastic rebar has the potential to displace steel as the most preferred reinforcing technology in a few years. These hemp rebars are partially guaranteed to eliminate corrosion challenges, and they are more durable than steel bars.

Rebar is a crucial component in the frameworks of cement buildings. They help construct perfectly standing and durable skeletal frameworks for convention infrastructure projects. On its own, concrete lacks tensile strength, and this is the primary reason why rebars are used—to provide tensile strength.

The Manufacturing Potential of Hemp

About 150 years ago, before the onset of cannabis prohibition and the criminalization of offenders, hemp was used to produce over 75% of the goods consumed by Americans. The manufacturing of hemp-derived goods was scrapped when the government banned the cultivation and usage of the drug based on the threat of abuse. Currently, hemp is at the forefront of manufacturing discussions due to its undeniable potential to serve humans and the global ecosystem.

At the crucial point of severe environmental degradation and climate change, an environment-friendly crop like hemp could be the world’s savior. Hemp is a biodegradable harvest crop that can derive recyclables, renewables, and reusable products. For products that can’t be recycled, they are guaranteed to degrade into the environment as quickly as possible. Environmentalists who are researching the benefits of hemp claim that the mass production of the crop could go a long way towards limiting global warming effects through the reduction of carbon monoxide compounds in the air.

The industrial use of hemp plants could help produce thousands of essential items needed for day-to-day activities, including plastics, paper, clothing, linen, and drugs. It could also produce several technological tools and building items like rebar.

Hemp and the Steel Industry

Studies at Rensselaer Polytechnic and other reputable institutions point out that hemp could be a perfect replacement for steel. These scientists claim these plants are phenomenal crops meant to be mass-cultivated on industrial scales to produce dozens of products.

For example, the various car parts produced from steel or plastic can be alternatively made from hemp. And hemp is a much stronger and more durable raw material than steel and plastic. Yes, hemp is stronger than both materials and products derived from the crop that have long-lasting lifespans.

The New Study

The preliminary study confirms that hemp possesses better strength capabilities than steel and has a higher chance of substantially reducing greenhouse gas emissions.

The Rensselaer Polytechnic Institute for Energy, Built Environment, and Smart Systems (EBESS) are in charge of this new research. The institute is committed to developing a broad strategy for a durable and cost-effective hemp industry to address the constant climate change challenges in a traditionally powered ecosystem. The institute is an interdisciplinary initiative that the private school believes will close the gap between business, engineering, and design.

Walczyk and Tsamis said the research was borne out of a need for innovative and affordable hemp technologies. They also stated that hemp rebar is not the only technology being researched. These other innovations include new hemp biocomposite processing techniques and the development of decortication technology to separate hemp fibers without reducing their mechanical properties.

More Details

Concrete does not possess the internal strength required to stand on its own without support. Construction workers and engineers use steel rebars to provide tensile or inner strength. Rebars are more sturdy rods, conventionally made from steel, but not long.

The research team at the private research university published that the newly developed hemp rebars can provide the necessary framework for building and infrastructural construction. They also stressed the non-corrosive properties of proposed rebars.

Hemp is not the only material that could replace steel for construction purposes. In 1958, Roger Bacon discovered that graphite whiskers possessed ten times more tensile strength than steel and three times its stiffness. After this discovery, graphite was used to make carbon fibers. Recent findings of hemp claim hemp fibers are much stronger than these carbon fibers.

Another notable material in construction is graphene. The Science Journal discovered that graphene sheets have at least a hundred times the strength of steel. The carbon variant is an excellent conductor of electricity and can be combined with polythene products to allow conductivity. It has also been used to produce super-energy batteries and electric vehicles. The downside to this material is the cost of production. Another reason hemp is famous. The plant mimics many features of graphene, steel, and graphite whiskers. It could store as much energy as graphene and has more tensile strength than steel, and can be mass-produced at cost-effective prices.

Note that for hemp to be mass-produced for day-to-day products and industrial tools or components, there are still a few technical challenges that must be overcome. Some of this includes developing efficient processing methods and equipment that would best fit the hemp materials, manufacturing methods, and property data. Failure to overcome these hurdles would result in low-quality hemp rebar samples, among others.

Bottom Line

Hemp can be used to bring multiple high-end products to reality at far lower costs than steel and other traditional production materials. The ongoing development and research on the potential usefulness of hemp plants will shed more light on this. Rensselaer’s Seed to City Hemp Initiative will not only place the school on the hemp industry radar but also contribute to the progress of the New York engineering, design, business, and hemp industries. This proposed natural fiber-reinforced thermoplastic rebar derived from hemp plants will keep hemp structures intact for a long time.

Note that steel cannot be replaced entirely in the industry because it remains the best option for producing some substantial items and electrical tools.

Building Low-Carbon Hemp Homes

Source: AZOBuild.com | Author: Reginald Davey | Aug 21, 2022

Building new structures from low-carbon and renewable resources is gaining significant attention both within the construction industry and wider society. This article will look at constructing new homes with hemp, a low-carbon, and sustainable material.

The Construction Industry: A Major Contributor to Climate Change

According to the World Economic Forum, the global construction industry contributes around 38% of total global carbon emissions. The number of buildings constructed worldwide every week could fill a city the size of Paris.

Approximately half the carbon emissions produced by a building during its serviceable lifetime are produced during its construction before people even use it. This is known as “embedded carbon”, and materials such as concrete and cement are estimated to be responsible for about 8% of total global carbon emissions.

The construction industry is also responsible for the exploitation of vast amounts of virgin, non-renewable resources, energy, and produces enormous amounts of waste materials during both construction and demolition. Nearly all the waste produced during a building’s lifetime is disposed of in the environment, typically in landfills, losing valuable resources which could otherwise be used to improve the sustainability and circularity of the sector.

Green Strategies in Construction

Recognizing the scale of the issue, the construction industry has focused on strategies to significantly reduce the carbon footprint of new buildings and infrastructure.

Several technologies have been explored in the construction industry, with renewable energy helping to reduce the carbon emissions from sites and being researched for use in the construction of raw materials. In the UK alone, three out of five construction firms have declared interest in using renewable energy sources such as solar or wind power.

Equipment is getting a green upgrade too. Companies have explored the use of environmentally friendly construction equipment, with Hyundai announcing the development of an excavator which is powered by hydrogen fuel cells, with plans to introduce this machinery in 2023.

One of the most interesting areas of sustainable construction is the use of alternative construction materials which can reduce the amount of embedded carbon in new buildings and infrastructure. Numerous sustainable materials have been investigated in studies over the past few decades, with varying degrees of success.

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Sustainable construction materials have made their way into the market over the past few years, displacing the use of conventional carbon-intensive materials such as concrete. Examples include geopolymer composites, recycled plastic, recycled wood, rammed earth, bamboo, wool insulation, living rooves, straw bale, Ferrock (a type of recycled material made from materials such as steel and dust), and hemp.

The Use of Hemp in Sustainable Construction

Hemp is an ancient construction material. Over the course of recent history, the use of hemp has been overshadowed by its association with its psychoactive cousin, cannabis. However, there has been renewed interest in the use of hemp for a variety of commercial products, including as a sustainable building material that can offer a low-carbon alternative to conventional materials.

Many building materials based on hemp have been developed by scientists in recent decades, which show excellent commercial promise. Hemp particleboards and chipboards use this eco-friendly plant-derived material and incorporate other fibers such as flax to produce a stronger, lighter, and more moisture-resistant alternative to conventional chipboard.

Hempcrete is a revolutionary concrete-like material that combines industrial hemp hurds (inner cores of hemp plant stems), water, and lime-based binders. Once applied and dried, hempcrete becomes a strong and lightweight building product that can be used in new homes.

Building homes with hemp | Freethink

Hempcrete offers advantages such as good insulation, less embodied carbon and energy, low flammability, mold and pest resistance, CO2 absorption during curing, increased strength over time, moisture resistance, non-toxicity, and full recyclability.

Hemp provides several benefits for the construction industry and is playing an increasing role in the sector’s net zero carbon aims to meet international climate change mitigation targets by 2050.

Case Study: Common Knowledge – Building Tiny Homes from Hemp

The potential of hemp as an eco-friendly and low-carbon construction alternative is vast, but one social enterprise in Ireland is championing the small benefits of this ancient building material. Teaming with Margent Farm, a hemp producer, Common Knowledge has designed a low-carbon tiny home using hemp.

They have stated that their tiny homes could help people struggling with the cost-of-living and housing crisis. Named Tigin Tiny Homes, they are essentially oversized caravans. Aside from corrugated hemp cladding panels, these homes are made from other sustainable materials such as cork for insulation and natural rubber for flooring tiles. They can be purchased pre-made or people can learn to build their own.

The hemp panels were first used in Flat House, a pioneering zero-carbon project and are constructed out of plant fibers and sugar-based resins from agricultural waste. Both are lightweight and extremely sustainable, and whilst planning regulations in the UK restrict their use in architectural products, this is less so when they are used in mobile construction.

Common Knowledge intends to make the plans for their Tigin Tiny Homes open source, which means that they would be free to use for anyone who wants to build their own. These plans would include architectural designs, materials lists, recommended suppliers, and pricing information.

In Summary

Hemp is an ancient building material that has garnered increased interest in recent years due to the need for sustainable alternatives to conventional materials such as concrete and the urgent requirement to reduce the construction industry’s carbon footprint and limit environmental damage. With innovative projects such as Common Knowledge’s Tigin homes, the future of hemp in the construction industry is looking promising.