What Is A Foam Concrete in Construction?
What Is A Foam Concrete in Construction?
Foam concrete is a lightweight, cement-based material made by mixing cement, sand or fly ash, water, and foam. It is typically in the form of a foam grout or foam mortar, and has a dry density ranging from 300 to 1600 kg/m3.
The compressive strength of foam concrete can range from 0.2 to 10N/mm2 or higher, and is differentiated from other types of concrete, such as air entrained concrete and aerated concrete, by the volume of air that is entrained in the mix.
In comparison, air entrained concrete contains 3 to 8 percent air, while retarded mortar systems contain 15 to 22 percent air and the bubbles in aerated concrete are chemically formed.
History Of Foam Concrete
Foam concrete is a building material that has been in use since the early 1920s, when it was first used as insulation in the form of autoclaved aerated concrete. In the 1950s and 60s, a detailed study was conducted on the composition, physical properties, and production of foamed concrete.
As a result of this research, new admixtures were developed in the late 1970s and early 80s, leading to the commercial use of foamed concrete in construction projects. Initially, it was used in the Netherlands for filling voids and for ground stabilization.
Further research in the Netherlands helped to increase the use of foam concrete as a building material. Today, foam concrete is made using a continuous foam generator, which produces a foam by agitating a foaming agent with compressed air to create “aircrete” or “foamcrete.”
This material is fireproof, insect proof, waterproof and offers excellent thermal and acoustic insulation. It can also be cut, carved, drilled, and shaped using woodworking tools.
Foam concrete is used to make foundations, subfloors, building blocks, walls, domes, and even arches that can be reinforced with construction fabric.
Composition Of Foamed Concrete
Foamed concrete is a type of lightweight concrete that is made by mixing a cementitious material, such as Portland cement, with water, sand and a foaming agent to create a mixture that is airy and lightweight. The resulting material has a number of beneficial properties including low density, good insulating properties and high compressive strength.
The density of foamed concrete can be adjusted by controlling the amount and type of materials that are used in its production. For example, using a higher amount of cement and a lower amount of sand or other fillers can increase the density of the resulting material.
On the other hand using a lower amount of cement and a higher amount of sand or other fillers can decrease the density.
It is important to note that the density of foamed concrete should not be too low, as this can compromise the strength and stability of the material. In general, foamed concrete with densities below 600kg/m3 is not recommended.
Advantages Of Foam Concrete
- Foam concrete has several benefits, including:
- It does not settle and does not need compaction.
- It is a lightweight concrete, reducing its dead weight.
- It has a freely flowing consistency when fresh, which helps it fill voids completely.
- It has excellent load-spreading and distributing capabilities.
- It does not impose significant lateral loads.
- It has low water absorption.
- It is easy to produce and quality control is simple.
- It has a high resistance to freezing and thawing.
- It is non-hazardous and leads to faster work completion.
- It is cost-effective and requires less maintenance.
Disadvantages Of Foam Concrete
- Some disadvantages of foam concrete are:
- Its sensitivity is due to the presence of water in the mixture
- Challenges in achieving a smooth finish
- Longer mixing time
- Reduced compressive and flexural strength at higher densities.
Applications For Foam Concrete
Foamed concrete is a type of lightweight concrete that can be used for a variety of purposes, including insulation for floors, roofs, and walls, as well as filling in trenches and voids.
It has a density range of 400 to 1600 kilograms per cubic meter and can have a 7-day compressive strength of 1 to 10 mega pascals. Foam concrete is also fire resistant and has good thermal and sound insulation properties.
Some specific applications for foam concrete include filling in bridge approaches and embankments, abandoned pipelines, and trenches, as well as being used as a sub-base for highways and for the creation of precast blocks, wall elements, and insulation boards.
In conclusion, Foam concrete is a lightweight material that can be used in a variety of applications in both residential and commercial projects. It is inexpensive, easy to install, and durable, making it an ideal choice for many types of construction and repair projects.
The unique composition of foam materials also makes it highly breathable, which makes it well-suited for controlling temperature in buildings.