Introduction of Bulk Density and % Voids of Coarse Aggregates

Construction materials are often classified based on their granular size. Coarse aggregates are particles greater than 4.75 mm, but generally range between 9.5 mm to 37.5 mm in diameter.Fine aggregates are particles with diameters less than 4.75mm. Bulk density is a measure of mass per unit volume of a material. The bulk density of an aggregate is the ratio of the mass of the aggregate to the volume of the container. The percentage of voids is the ratio of the volume of the voids to the total volume of the sample. It is important to know the bulk density and percentage of voids of an aggregate because they affect the strength and performance of concrete.

What Is Bulk Density and % Voids of Coarse Aggregates

• The bulk density of coarse aggregates is the mass of the aggregates per unit volume
• The % voids of coarse aggregates is the percentage of the volume of the aggregates that is voids.

What Is Bulk Density and Their Types

• Bulk density is a property of powders, granular materials, and other “divided” solids, especially used in reference to mineral components (soil, gravel), chemical substances, (pharmaceuticals, food ingredients), or other agricultural, industrial, or consumer products
• Two types of bulk density are often determined: loose bulk density and compacted bulk density.

  Loose bulk density is the ratio of the mass of an untapped powder or granular material to its volume including the interstice spaces within the sample

• It is expressed in grams per cubic centimetre or pounds per cubic foot.

  Compacted bulk density is the ratio of the mass of a tapped powder or granular material to its volume including the interstice spaces within the sample

• It is expressed in grams per cubic centimetre or pounds per cubic foot.

Types of Bulk Density of Coarse Aggregate

• There are three types of bulk density of coarse aggregate – loose, compacted, and submerged
• The loose bulk density is the measurement of the aggregate in its natural form
• The compacted bulk density is the measurement of the aggregate when it is firmly packed together
• The submerged bulk density is the measurement of the aggregate when it is submerged in water.

Types of Coarse Aggregate According to Packing

• Coarse aggregates are classified according to their packing
• The three types are:

  1

• Loose pack: This is the simplest type of packing, in which the aggregates are not tightly packed together.

  2

• Medium pack: This is a more dense packing, in which the aggregates are packed together more closely.

  3

• Tight pack: This is the most dense packing, in which the aggregates are packed together very closely.

Conclusion

The bulk density of coarse aggregates is the weight of the aggregates that is required to fill a container of a specified unit volume. The percent voids of coarse aggregates is the percentage of the volume of the container that is not occupied by the aggregates. The bulk density and percent voids of coarse aggregates are important properties that are used to design asphalt mixtures.

Frequently Asked Questions

What is the bulk density of coarse aggregates?

The bulk density of coarse aggregates is the mass of the aggregates per unit volume.

bulk density coarse aggregate?

The bulk density of coarse aggregates is the weight of the aggregates that is required to fill a container of a specified unit volume. The percent voids of coarse aggregates is the percentage of the volume of the container that is not occupied by the aggregates.

What is the importance of knowing the bulk density and percentage of voids of an aggregate?

The bulk density and percentage of voids of an aggregate are important properties that are used to design asphalt mixtures.