Posted on September 20, 2023
Sustainable Practices In Concrete Construction
Concrete is the world’s most widely used building material, but it comes with serious environmental costs. It consumes large amounts of natural resources and produces harmful greenhouse gases.
However, sustainable construction practices can help mitigate these impacts. Strategies include using recycled materials, reducing cement content, and incorporating sustainable additives. Designing long-lasting structures that require less maintenance also helps reduce resource use. Visit https://concretecontractorcoloradosprings.com/ for more information about sustainable construction.
Using Recycled Materials
As the world’s most used building material, concrete has a major impact on our environment. But it can be made more sustainable. The use of recycled materials in concrete construction helps reduce reliance on finite natural resources and minimizes the environmental impacts of extraction and transportation of new aggregates. It also reduces the amount of waste that ends up in landfills. Recycling concrete is one of the most effective ways to help combat climate change and promote sustainability.
Commercial concrete contractors are increasingly using recycled materials, such as crushed glass and demolished masonry, as part of the mix design for their projects. By incorporating these, along with other recycled materials, such as steel and rebar, into their mixes, they can reduce the amount of new aggregates that need to be extracted from the earth and transported. This can result in significant reductions in a project’s carbon footprint.
When a concrete structure is nearing the end of its life, it can be broken down and reused in other applications, such as road works or as aggregate for new concrete mixes. This process, known as concrete recycling or C&DW (construction and demolition waste), is a key component of the green movement in the construction industry. In addition to avoiding unnecessary landfill of useful materials, it can also save on tipping fees, which are usually based on weight and/or volume, since less virgin materials need to be moved to disposal centers.
The main source of emissions in the production of concrete is cement, and this can be reduced significantly by using alternative binders and/or reducing the overall cement content in the concrete mix. The energy performance of concrete is another important aspect that can be improved. Building and pavement systems with good thermal performance can lead to a 50% reduction in embodied emissions by 2050 compared to 2016.
In addition, the use of recycled concrete can reduce a project’s energy costs. This is because the concrete does not rust or require regular painting, and it has good insulation properties that can make structures more efficient to heat and cool.
Using Renewable Energy
Concrete is durable, insulating, and energy-efficient, which makes it an excellent choice for climate-resilient construction. However, its colossal carbon footprint needs to be reduced. Cement production is responsible for 8% of global human-caused greenhouse gas emissions.
Fortunately, concrete can be made more sustainable by using recycled materials, optimizing production processes, and incorporating environmentally friendly additives. This approach has the potential to reduce both carbon emissions and costs.
The cement used in concrete is produced by burning fossil fuels, which generates carbon dioxide. By replacing coal with alternative fuels or using renewable energy to power plants, the cement industry can significantly decrease its CO2 emissions.
In addition, the use of recycled aggregates and other eco-friendly materials in concrete production reduces the demand for virgin materials. This can also help divert waste from landfills, which is a significant source of carbon emissions.
The concrete industry can also minimize its CO2 footprint by switching to electric mixers, which operate on renewable electricity and can cut CO2 emissions by up to 30 percent. The transport of concrete from the plant to the construction site is another major source of CO2. By using electric trucks, this could be reduced by up to 80 percent.
Some companies are even working to make concrete itself more sustainable. One company has developed a process that injects recycled carbon dioxide into the mix to create a mineral compound that acts as an aggregate and increases the concrete’s strength.
This technology still has a long way to go before it’s ready for commercial use, but it shows how the concrete industry can make a positive impact on our environment. As the world’s most popular building material, concrete can play a vital role in the effort to reduce climate change, and the industry must work to ensure its sustainability.
Unlike wood, which requires vast tracts of monoculture land to grow, concrete can be manufactured locally, which cuts down on transportation costs and reduces greenhouse gas emissions. Furthermore, concrete’s durability and energy efficiency mean it can last longer than other building materials, reducing the need for demolition and replacement.
Using Low-Carbon Concrete
Concrete has been used in buildings, roads, and bridges for centuries. Structures made of concrete have survived wars and natural disasters and outlasted the civilizations that built them. Unfortunately, making all that concrete has a major impact on our climate, generating gigatons of carbon dioxide emissions every year. The good news is, the industry has been focusing on carbon reduction initiatives to address this challenge.
Using alternative materials, optimizing construction processes, and switching to renewable energy sources can all help reduce the embodied carbon footprint of concrete. The most important change, however, lies in changing the cementitious material that makes up the bulk of concrete structures. This is where the biggest opportunities for reduced embodied carbon exist.
To produce traditional concrete, a binder, called cement, is mixed with sand, gravel, or crushed stone in a concrete mixer until the mix has a fluid consistency. This is typically a mixture of cement (CEM1) and secondary cementitious material, such as fly ash, GGBFS, or granulated blast furnace slag (GBFS). In addition to sand, gravel, or crushed stone, concrete can also contain additives such as polymers and fibers, which increase strength, durability, water resistance, and abrasion resistance. The binders and additives all have different embodied carbon content, with CEM1 having the highest level.
A few innovative companies are reducing the embodied carbon of concrete by using different cementitious material mixes and/or replacing some of the CEM1 with recycled or alternative binders. For example, one company produces ground glass pozzolans. This alternative to fly ash and GGBFS uses post-consumer and industrial waste glass that cannot be recycled in other recycling streams and has approximately half the global warming potential of CEM1.
Another company, Blue Planet, captures carbon dioxide from flue gas at power plants to make a synthetic aggregate for concrete. This process uses significantly less energy and does not require the purification of CO2 that is needed in traditional methods. The company also captures CO2 from the concrete cure process and locks it away forever, producing low or even negative-carbon concrete.
Using Alternative Materials
Concrete is the most used manufactured material on the planet, and it’s no secret why. This versatile, durable, and cost-effective material forms the foundations of cities, connects communities, and will continue to play a vital role in meeting the construction needs of an ever-growing population.
However, the production of cement, a key ingredient in concrete, accounts for about 8% of the world’s CO2 emissions and is associated with other environmental costs, including deforestation, water scarcity, and the often deadly conditions under which it is mined by so-called “sand mafias.” The good news is that there are ways to reduce the carbon footprint of concrete while still preserving its incredible properties.
Increasingly, commercial concrete contractors are using recycled and other alternative materials in their construction projects. Using recycled aggregates and eco-friendly binders not only helps reduce the overall environmental impact of concrete production but also conserves natural resources by diverting waste from landfills, promoting a circular economy mindset. This approach is a step towards sustainable concrete that can help achieve the goal of net-zero carbon emissions by 2050.
Another way to reduce the carbon footprint of concrete is by reducing the amount of cement that goes into each mix. This can be done by using lightweight recycled and/or other alternative materials as aggregates, reusing precast concrete and other construction waste products, and employing water-reducing admixtures. These techniques also contribute to lower energy consumption during concrete production, thus further decreasing the carbon footprint of a finished product.
Local governments can also use concrete alternatives, such as timbercrete and ashcrete, to save money on construction costs while promoting sustainability. These materials use a variety of renewable and recycled sources to produce and require less energy than traditional concrete, making them more environmentally friendly. Additionally, they provide excellent fire resistance and do not emit noxious gases during combustion. They are also a good choice for buildings in seismic zones as they can absorb and resist the motion of the ground without losing their structural integrity. Lastly, because these materials do not rust or burn, they do not need to be replaced or resurfaced frequently, reducing the long-term maintenance and replacement costs of buildings.