Lightweight concrete is one type of material that will make your job much easier. This concrete is mainly composed of constituents that make it lighter, which makes it much less heavy than ordinary concrete and therefore, much more practical to use. Heavy materials found in conventional concrete such as aggregates are replaced. Instead, it is possible to add polystyrene beads for example. This characteristic makes this concrete very useful in the realization of certain types of works such as for foundations or in insulation.
Characteristics Of Lightweight Concrete
Lightweight concrete Selangor therefore differs from other types of concrete, in particular by its much lower weight than conventional concrete. Once dry, it has a density that can range from 300 to 1800 kg / m³, while ordinary concrete is rather between 2000 and 2300 kg / m³.
There Are Two Categories Of Lightweight Concrete:
Lightweight structural concretes: they are given mechanical resistance. They comply with the concrete standard NF EN 206 / CN. Their density is between 800 kg / m3 and 2000 kg / m3.
Lightweight non-structural concrete: they have no guarantee of mechanical performance.
How Do You Get Lightweight Concrete?
Lightweight concrete is obtained by incorporating air “voids” into the material.
These Voids Can Be Located:
Inside aggregates, when using lightweight aggregates: this is the most common technique for making lightweight concrete. All or part of the current aggregates (gravel and sand type aggregates) are replaced by light aggregates. Many special aggregates can be used to make lightweight concrete. The choice of the type of aggregate depends on the desired density (see table below).
Between the aggregates, in the case of cavernous concrete: by removing a large part of the sand, we then obtain a lightweight so-called cavernous concrete, containing a lot of voids.
In the cement paste, in the case of foam concrete or cellular concrete: thanks to specific additives, a large quantity of air is introduced into the cement paste.
The Main Advantages Of Lightweight Concrete Are:
Low weight: lightweight concrete weighs between 100 and 1800 kg / m3.
Thermal insulation: the thermal insulation of concrete structures is greatly improved thanks to the low thermal conductivity of lightweight concrete which, for the lightest (light screed), can drop to 0.1 W / m ° K (compared to 1, 75 W / m ° K for traditional concrete).
These weight and thermal insulation gains linked to the presence of more or less large quantities of air in the aggregates or in the paste of lightweight concrete, result in a reduction in mechanical resistance. The lighter the concrete, the lower its mechanical resistance. This trend is illustrated in the following table. At the same time, the lighter the concrete, the more its thermal conductivity is reduced and therefore the better its thermal insulation capacity.
The Other Interesting Properties Of Lightweight Concrete Are:
Good acoustic performance, in particular in terms of sound absorption thanks to their very alveolar structure.
Better fire resistance: thanks to their low thermal conductivity and their slightly reduced coefficient of thermal expansion.
Better elasticity (damping of impact noises) linked to their reduced deformation modulus, in particular for lightweight expanded polystyrene concrete.
Great ease of implementation and work after hardening: it is possible to saw, drill, nail lightweight concrete with traditional tools (particularly cellular concrete, foam concrete and cellular concrete).
Good frost resistance due to their cellular structure.