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Concrete Contractors Colorado Springs can take our civilization skywards and push it outwards, swallowing up fertile topsoil and choking habitats. That is why architects are increasingly turning to eco-friendly materials to reduce the environmental impact of their buildings.
The aim is to lower the embodied energy in concrete by using supplementary cementitious materials (SCMs) such as fly ash and slag cement and by utilizing higher-strength concrete.
Aggregate is the granular portion of concrete that provides structure and strength. It contains various materials such as sand, gravel, crushed stone, slag, and recycled concrete. Construction aggregates are used in road building, commercial construction, and industrial applications. They are an important component in any project because they provide concrete support. The type of aggregate used has a significant impact on the performance and durability of the final tangible product.
Recycled concrete aggregate (RCA) is a green alternative to conventional aggregates for concrete production. RCA is created by collecting material from construction and demolition waste (CDW). This material undergoes a series of processes to convert into an acceptable construction material. These include crushing, screening, and grading. In addition, it is subjected to strict quality controls to ensure that the material meets the appropriate specifications for use in concrete.
Using RCA reduces both the consumption and waste of natural mineral resources. It also helps to conserve landfill space. In addition, using RCA is a way to comply with the LEED Green Building Rating System. The system’s credit 4 requires a minimum of 25% of the building materials to be recycled or “post-consumer” materials.
The properties of RCA are comparable to those of conventional aggregates. RCA has a higher water absorption rate than natural aggregates but is less affected by temperature changes. This characteristic makes it an ideal replacement for natural sand. It also has better wear resistance and more stable permeability than natural aggregates.
On the other hand, RCA is more susceptible to carbonation and chloride penetration than natural aggregates. Moreover, it has lower density and mechanical strength. Furthermore, it has higher porosity and water absorption, making it unsuitable for high-strength concrete use.
Allied has conducted an in-depth review of several states’ transportation agencies’ usage of RCA for concrete. The process involved a meeting with agency staff to discuss applications used in each state and interviewing them on their experience using the material. The review team included Allied’s engineering, environmental, design, and materials department representatives.
Concrete is one of the world’s most popular construction materials, yet it also contributes substantial embodied carbon. Some estimates put the industry’s contribution at 10 percent of global carbon emissions. Fortunately, engineers have a range of impressive, cost-effective solutions to reduce the environmental impact of concrete.
Some manufacturers are trying to reduce this carbon footprint by using alternative heat sources. The most common replacement is ground granulated blast-furnace slag, but waste glass is another option. Another way to lower a plant’s carbon footprint is to use recycled aggregate, which reduces the need for virgin material. This approach can cut a concrete plant’s carbon footprint by about 40 percent.
Several companies are working on even more dramatically reducing concrete’s environmental footprint. For example, CarbonCure Precast injects recycled CO2 into concrete as it’s being mixed, causing a chemical reaction that increases the strength of the finished product. This approach not only cuts the carbon footprint of the concrete, but it can also earn a building company a green premium that can improve its market position.
Electrifying the lime kilns used to make Portland cement is another possibility. The kilns are almost entirely fossil fuel heated, and switching to electricity would cut emissions dramatically. This move is particularly important because it would enable the kilns to take advantage of renewable energy, which can be produced in a more environmentally conscious manner.
Using less concrete is an obvious way to reduce the environmental impact of buildings, and some builders are now offering to specify low-carbon concrete for their projects. Some of this low-impact concrete is made with a blend containing no Portland cement. In contrast, others use a material called Fly Aggregate, which has the same structural characteristics as traditional concrete but doesn’t require the same heat to set.
Water-reducing agents are a class of concrete admixtures that decrease the amount of water needed to achieve a given slump while maintaining the workability of the mix. They are usually anionic surfactants, such as lignosulfonate or naphthalenesulfonate formaldehyde polymer, and can disperse cement particles to make the concrete flow easier. The result is a lower water-to-cement ratio, saving cement and lowering contractor costs.
They also mitigate drying shrinkage, reducing cracking and deformation. These benefits make them ideal for large concrete pours or structures with restrained conditions. Additionally, water reducers extend the workability of the concrete, allowing it to be transported and placed over longer distances or timeframes.
These admixtures also improve the cohesion between cement particles and reduce segregation and bleeding, making them ideal for high-strength, low-slump concrete. Finally, they can help improve the mix’s durability, reducing freeze-thaw damage and other long-term concerns.
While the first water reducer was developed in 1932, researchers at GCP Applied Technologies continue refining this technology. They recently introduced an innovation to the ready mix industry that can remotely manage concrete slumps between the plant and the job site using smart technology.
The benefits of these innovations are hugely significant for sustainability. By optimizing mix designs, utilizing SCMs like fly ash, GGBFS, and silica fume, and reducing the amount of water used in concrete production, you can dramatically minimize the environmental impact of your next construction project.
In addition, sourcing local materials and using lean manufacturing practices promotes resource efficiency by eliminating transportation-related emissions and supporting the local economy. Additionally, utilizing industrial byproducts and implementing just-in-time production ensures that materials are only used when required, minimizing storage requirements and waste. As more research is conducted, these advancements will allow the industry to develop eco-friendly concrete that meets or exceeds the performance of traditional materials. Ultimately, this can reduce maintenance and repair needs for sustainable buildings and structures that will last for generations.
Concrete is a popular building material and a major component of modern infrastructure. However, during its manufacture, it creates large amounts of carbon dioxide as a chemical byproduct and in the energy needed to power the reactions that make it. Concrete producers can significantly reduce these emissions by replacing some of the cement in their mix with sustainable concrete admixtures, such as fly ash, silica fume, and ground granulated blast furnace slag (GGBFS). These materials are also often cheaper than OPC and aggregate.
Using these alternative concrete admixtures in conjunction with oil can further cut a project’s carbon footprint. Form oil is a non-staining hydrocarbon product that prevents the concrete from adhering to metal and wood forms, which are used to shape the concrete while it cures. For years, mineral oil has been the standard form release agent, but organic and synthetic oils are now gaining popularity as alternatives.
When used properly, form oil prevents the concrete from adhering to wooden and metal forms and allows for quick and easy removal of the formed concrete. It also helps to protect the forms from rust and corrosion, which increases their life.
In addition to reducing environmental impacts, using form oil can reduce construction time by up to 40 percent. This reduction in time translates to reduced energy consumption during the construction process and a lower operating cost for buildings made with precast concrete.
Sustainability is a holistic approach to balancing economic and social needs, manipulating long-term development and endurance while protecting the environment. Concrete manufacturers can achieve this by utilizing environmentally friendly raw materials and incorporating innovative production techniques, such as precasting.
Precast concrete is usually manufactured close to where it will be erected, decreasing hauling distances and fuel consumption and exhaust levels. In addition, the concrete’s thermal mass stores and releases heat slowly over time, which can result in substantial energy savings for the building owner, especially when combined with insulation. This energy conservation is a key factor in sustainability.