Types of Aggregates and Their Characteristics

Aggregates are granular materials, such as sand, gravel, crushed stone, crushed hydraulic cement concrete, or iron blast furnace slag, that are used with a hydraulic cementing medium to produce concrete or mortar. Aggregates can be divided into two main categories: coarse-grained and fine aggregates. Each type is further subdivided into many types based on classification. The sieve analysis technique is used to determine the gradation of aggregates for use in specific applications.

Gravel, sand, and crushed stone are classified as standard or normal aggregates. For greater workability and economy, fine aggregates should have a rounded shape. Angular aggregates provide better interlocking properties in concrete, which contributes to the strength of the concrete. Aggregates make up about 70-80% of the total volume of concrete.

They reduce the amount of water needed for a concrete mix, which can also reduce workability but improve its innate strength. Some natural aggregate deposits known as pit gravel consist of gravel and sand that can be easily used in concrete after minimal processing. Aggregates are essential for many construction projects, from large-scale commercial works to smaller domestic works. Scaly aggregates are those whose thickness is smaller compared to length and width or other dimensions.

When the minimum dimension of the aggregate is less than 60% of its average dimension, then it is called a flake aggregate. If you need specific advice on the type of aggregates needed for your needs, it's helpful to talk to professionals. Natural aggregates are generally used in their natural state with rock fragments or after mechanical processing such as crushing, washing and sizing. The properties of aggregates depend on the bedrock, which can be igneous, sedimentary or metamorphic. Aggregate is called a bonded material when mixed with cement or binder materials and is called a non-bonded material when used without cement or binder materials.

Leave Message

Required fields are marked *