Concrete is the most used construction material in the world. It is a composite material made up of aggregates, cement and water. The total combination of aggregates results in the density of the concrete. All hard, natural materials such as gravel or crushed stone can be used as aggregates. Cement is a binding agent that holds concrete together and gives it strength.
There are two types of cement: Portland cement and mixed cement. Portland cement is made from clinker (a type of rock) and limestone. Mixed cement is made from clinker, limestone and other materials such as fly ash or slag.
Why is concrete density important?
The density of concrete is an indication of the weight of the structure and also the properties of the concrete.
In general, the greater the density of concrete, the greater its resistance.
The durability of concrete, porosity of concrete, permeability of concrete, etc. are directly related to the density of the concrete. Depending on the type of structure, we determine what type of concrete to use. Hence, the density of the concrete comes into play.
Additionally, higher density concrete is used in most major structures. Low density concrete generally has low strength. Depending on the strength requirements and other aspects such as Durability of concrete selection is carried out.
Factors Affecting Concrete Density
The two main factors that affect concrete density are the type of aggregate and mixing proportions.
Density is determined by the type of aggregate used, as different types of aggregate have different densities. For example, if a mix contains pea gravel as an aggregate, it will have a lower density than if it contained crushed granite.
Use of Lightweight Aggregate Lightweight natural aggregates obtained from industrial waste and lightweight artificial aggregates such as volcanic ash, lightweight sand, etc. produce low density concrete. We can produce normal concrete using other common types of concrete.
Mixing ratios also affect density because they determine how much water is added to the different aggregates. If too much water is added to a mixture containing crushed granite, the mixture will be too liquid and will not be dense enough for construction purposes.
Furthermore, the use of high-density material in the concrete mix also increases the density of the concrete. This is directly related to the use of different types of aggregates with different densities.
High Density Concrete
Keywords: Use of heavy aggregates, use of additives such as steel fibers
The use of high-density concrete is beneficial to the construction industry. For many projects it represents a more sustainable and economical solution.
Since concrete has high compressive strength, denser concrete contributes more to compressive strength.
This can reduce the weight of the concrete and make it more durable. The weight reduction would affect the compression element if higher quality concrete and smaller cross sections were used. However, this largely depends on the respective conditions.
The use of high-density concrete has increased in recent years as it becomes increasingly popular among architects, engineers and contractors.
Bulk Density of Concrete Definition
The density of concrete is called the apparent density of concrete. It is also known as the unit weight of concrete. These changes are based on the different units.
The apparent density of concrete is a measure of the mass per unit volume.
Bulk density = mass of concrete / volume of concrete
Units depend on usage and some units are kg/m 3 Pounds/ft 3 etc.
Bulk density can be expressed in pounds per cubic foot, kilograms per cubic meter, or grams per cubic centimeter.
The unit weight of concrete may be in kN/m 3 or a similar natural unit.
Bulk density is a measure of weight per unit volume. It is calculated by dividing the total weight of a material (in kilograms) by its total volume (in cubic meters).
Different densities of concrete
The most commonly available concrete densities are
- 20kN/ m3
- 24kN/ m3
- 25kN/ m3
- 26kN/ m3
