Different types of aggregates

Types of aggregates

These are of the following types.

1. Natural.
2. Artificial.

Natural

These are further divided into:

1. Coarse graded.
2. Fine graded.

Coarse graded

Those which retain on sieve # 4 are known as coarse aggregates.

Coarse graded consists of continuous grading of sizes. But mainly it consists of coarse sizes. A coarse aggregate of uniform size known as macadam, received its name from a Scottish engineer John Macadam. He first used it in asphalt mix.

Fine graded

Those which passes through sieve # 4 and retain on sieve # 200 are the fine aggregates.

Fine graded have a predominance of fine sizes.

Filler

Those which even passes through sieve # 200 are known as Filler.

Artificial

To achieve special strength, we make special aggregates which are known as artificial. These are used to gain high strength. As naturals have not enough strength.

Soft aggregates

Those which breakup due to single jerk are known as soft. For example shale.

Hard aggregates

Those which do not breakup on a single jerk are known as hard. For example granite.