Aggregate is a general term for coarse and fine granular materials such as sand, gravel, crushed stone, or slag. It can be naturally sourced (riverbeds, seabeds, quarries) or artificially manufactured (recycled concrete, expanded clay, blast furnace slag). In concrete, aggregates make up 60–75% of the total volume, making them essential for structural applications.

2. What is Aggregate Used For?

Aggregates are used to increase the strength, reduce the cost, and enhance the durability of construction materials. When mixed with cement and water, they provide volume and structural integrity. They reduce shrinkage and cracking, improve thermal properties, and help in evenly distributing loads in structural elements.

3. How Does Aggregate Work?

Although aggregates do not chemically react in the concrete mix, they act as a skeleton or framework. Cement paste binds the aggregates together. The interlocking particles increase mechanical strength and durability. Proper gradation of aggregate sizes improves packing density and reduces voids, enhancing strength and reducing water demand.

4. Where is Aggregate Used?

  • Concrete production (ready-mix and precast)

  • Asphalt mixtures (roads, bridges, runways)

  • Fill material in construction

  • Drainage systems

  • Railway ballast

  • Paving stones, curbs

  • Landscaping and decorative works

🔹 AGGREGATE SIEVE

1. What is an Aggregate Sieve?

An aggregate sieve is a mechanical or manual tool used to classify aggregates by particle size. It typically consists of a series of stacked metal mesh screens with decreasing openings from top to bottom. These sieves are manufactured according to international standards such as ASTM, EN, or ISO.

2. What is an Aggregate Sieve Used For?

Sieves are primarily used to determine the particle size distribution of aggregates. This distribution affects workability, strength, and durability of concrete or asphalt. Sieving is a vital part of quality control testing in material production and construction processes.

3. How Does an Aggregate Sieve Work?

A sample of aggregate is placed on the top sieve of a stack and subjected to mechanical vibration or manual shaking. As the material passes through each sieve, particles smaller than the mesh fall through to the next level while larger particles are retained. The weight retained on each sieve is measured to calculate the percentage of each size fraction.

4. Where is an Aggregate Sieve Used?

  • Construction and materials testing laboratories

  • Concrete batching plants

  • Asphalt production facilities

  • Aggregate manufacturing plants

  • Mining and quarrying operations

  • Educational and research institutions

  • Public infrastructure quality control units