Concrete is one of the most widely used construction mate-rials in the world. The production of concrete, notably it’s most important ingredient, cement, poses several sustainability issues that need to be managed. Significant amounts of coal are used in the kilns to make clinker, which is the major component in cement. Electricity is needed to run the machinery for grinding and blending in order to make the clinker and then to process it with other materials into cement. The whole production process emits large amounts of greenhouse gas (GHG) emissions and the quarrying of raw materials produces local impacts such as noise and dust.
Because of limited natural resources, concern over GHGs, it is necessary to look for sustainable solutions for future concrete construction. The future viability of the concrete community will be determined by its response to the global issue of sustainability. New research and technology, and the rapid development of the green building movement clearly point out that change in current life styles are essential if we are to maintain and improve our way of life. One of these changes includes the use of materials that will extend the service life of concrete and additionally make concrete a contributor to the more efficient use of energy and raw materials.
A sustainable concrete structure should have a very low inherent energy requirement, be produced with little waste, produce durable structures, have a very high thermal mass while leading to lower carbon emissions. One such alternative that comes close to the above description is cellular concrete.
Cellular concrete, also known by many other names such as aerated concrete, air-cured lightweight concrete, autoclaved cellular concrete, cellular light weight concrete and cellular light-weight, is engineered, low-density concrete with versatile features that can solve several construction, mining, and manufacturing challenges.
Cellular concrete is more durable when compared to traditional insulating materials, especially when considering potential chemical / fire exposure such as in process facilities. Compressive strengths are typically greater than four times that of plastic foam. It also has fireproofing, insulation, sound attenuation and energy absorbing characteristics.
Cellular concrete is a lightweight construction material consisting of Portland cement, water, foaming agent, and compressed air. The foam is formulated to provide stability and inhibit draining (bleeding) of water. Pozzolans, such as fly ash, and fibers are often added to the mix to customize compressive and flexural strengths. Cellular concrete typically contains no sand or aggregate. By trap-ping air bubbles within the concrete, a lightweight, insulating material is formed.
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