As we know that, an aggregate is a basic unit in the concrete.The role of aggregate is to resist the load acting on the concrete.Here I am going to describe the types of aggregate used for the construction process.
On later topics, we had described a lot of building materials used for construction.If you don’t know about building materials please read it.
Coming to our topic on types of aggregates, we use different classification of aggregates with various processes.Basically, we use aggregate for making mortar and aggregate.
We know that In a mortar, we use fine aggregate and in concrete, we use coarse aggregate for the building purpose.These are the main classification of aggregate that is used in civil engineering studies.But we will discuss other types of aggregate also.Let’s see
Types of Aggregate
As we mentioned above, the main classification of aggregate is fine and coarse aggregate.But the other types are cinder aggregate and broken brick coarse aggregate
The fine aggregate used for making mortar is silt and clay.The particle size of silt and clay is less than 4.75mm.Highly organic clay is also included in this classification.they are dark in colour, fibrous and bad odour.
The other classification of fine aggregate is based on the compressibility, that is highly compressible, intermediate and low compressible.
Based on compressibility there are 6 types of fine aggregate can be classified based on the plasticity chart.They are
- Highly compressible silt
- Intermediate compressible silt
- Low compressible silt
- Highly compressible clay
- Intermediate compressible clay.
- Low compressible clay.
Based on the particle size distribution
Based on the particle size distribution the fine aggregates are classified by grade zone
- 1st grade zone
- 2nd grade zone
- 3rd grage zone
- 4th grade zone
The coarse aggregate has a size greater than 4.75mm.They should be hard and strong.They may be crushed or partially crushed gravel which is retained on 4.75mm.
Coarse aggregate is used for making concrete and other functions are almost same as that of fine aggregate.The particle size analysis is done by using gradation curve of sieve analysis curve.Flaky and elongated aggregate should be avoided.
3.Broken bricks coarse aggregate
Broken brick coarse aggregate is another type of aggregates used for construction.They are prepared by overburnt bricks and they are used to make lime concrete.
The aggregate impact value should not exceed 50percent and water absorption should be less than 25percent.
The last classification of aggregate is cinder aggregate is used for making lime concrete.They are made from well-burnt furnace residue.