The materials that go into construction projects make up a significant portion of the project cost. But new innovations in materials are making it easier for companies to reduce costs without sacrificing quality.
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Insulated Concrete Forms
Insulated Concrete Forms (ICF) are a type of construction that uses interlocking foam blocks to create the walls and floors of a home or building. They are then filled with concrete to produce the permanent structure. ICFs are becoming increasingly popular due to their energy efficiency and disaster resilience properties.
ICFs have a long history of use, with the first being developed after World War II. These were blocks of treated wood fibers bonded with cement, but later versions used polystyrene foam. They are now manufactured by a number of companies and are available in a variety of shapes and sizes. The ICF blocks connect to each other somewhat like Lego bricks and provide a great deal of flexibility in the construction process.
These insulated concrete forms can be installed in a variety of ways, but the most common is to simply stack them up and pour concrete between. This can be done on site with minimal time and labor, and it is much faster than conventional construction methods. The concrete can then be poured into the holes of the ICFs, and it will bond with them, creating a stronger, more durable structure.
ICFs also have a number of other benefits for homeowners and builders, including their ability to cut costs over the life of the building. This is because the concrete and foam combination provides a very high R-value, which keeps heat from escaping in the winter and air from escaping in the summer.
3D-Printed Concrete
With the construction industry facing skyrocketing prices, shrinking labor force and growing housing demand, innovative methods are needed to solve these challenges. One such method is concrete 3D printing, which uses robotically controlled machines to construct building components. This technology can create structures in layers that are reinforced, insulated and cast. The resulting building is both faster and more cost-effective than traditional methods, according to Visiongain.
Currently, several companies are using concrete 3D printers to build houses and other large buildings. These printers work by nozzle jetting concrete, with each layer of printed material being deposited onto the previous layer. The printers use concrete mixtures that have been designed to flow easily through the nozzle. This allows the printer to eject concrete with a high strength, while maintaining a low rate of deformation during construction.
Another innovation in concrete printing is a technique called binder jetting, which combines concrete with binders like plastic, foam or resin. This method has been used to produce small furniture pieces such as the Root Chair and coffee tables, as well as larger architectural parts, such as the Radiolaria pavilion designed by KOL/MAC LLC Architecture + Design in 2009.
However, it’s not clear whether or not these concrete-printing techniques will replace traditional construction methods, particularly for horizontal structures such as walls. According to WSP, the challenges of incorporating these technologies into existing building codes can be significant, and a number of jurisdictions have not yet approved them for use in construction.
Self-Healing Concrete
Concrete is a popular building material that’s used in everything from road bridges to skyscrapers. It’s strong and durable, but it can crack under stress or changes in temperature or humidity. Scientists are working on ways to make concrete self-healing so that it can repair itself before damage becomes a problem.
Researchers at the USC Viterbi School of Engineering have found a way to replace the rocklike aggregates that help create concrete’s strength with engineered ones that also contain healing agents. The new aggregates are designed to fill in and heal cracks, avoiding the need for costly structural repairs.
Previous approaches to self-healing concrete involve adding chemically activated bacteria to the concrete. These bacteria react to cracks and produce limestone that helps repair them. Another method involves embedding microcapsules in the concrete that contain healing chemicals that are activated when they encounter a crack. These microcapsules can be expensive to manufacture, however.
Autogenous self-healing is a promising approach that uses the concrete’s own properties to repair cracks and damage. It works through a series of wetting and drying cycles, which enhances the tensile strain capacity of cracked ECC and FRCC. Additionally, the use of supplemental cementitious materials (SCMs) like GGBS, fly ash and silica fumes and expansive minerals such as MgO, calcium sulphoaluminate (CSA), quicklime and bentonite clay increases the self-healing performance of concrete.
Biodegradable Concrete
As consumers become more eco-conscious, they want products that have less impact on the environment. For concrete producers and contractors, this means utilizing materials that are biodegradable, have low VOC exposure limits and/or contain recycled ingredients.
The use of recycled aggregates reduces the amount of new materials that need to be created and used in concrete production. This also helps to conserve natural resources and minimizes the energy used to extract raw materials.
For example, a team from the DART Lab at the University of Michigan has developed a material that is comprised of sawdust and biopolymers. This material is then moulded or 3D-printed into the shape of a concrete formwork. This is an effort to mitigate the amount of wood waste produced during concrete construction. The team has successfully tested its ability to make a 1.8-metre structural column, and it can be reused up to 25 times.
Another recycled ingredient that is gaining popularity in concrete construction is post-consumer glass. This is an inert material that can replace up to 20% of traditional aggregates without affecting the final strength of the concrete. In addition, it has the added benefit of reducing consumer landfill waste. Other innovative eco-friendly building materials include slag from thermal power plants and fly ash.