Fine aggregate is a type of aggregate used in concrete that is smaller than 4.75 mm in size. It is typically made up of sand, crushed stone, or recycled concrete, and is used to fill the voids in the concrete mixture, provide a smooth finish, and improve the workability of the concrete. Fine aggregates are typically classified based on their size, shape, and texture.
- Size: The size of fine aggregate is typically measured in millimeters, and it can range from 0.075 mm to 4.75 mm in diameter. The most common sizes of fine aggregate used in concrete are 2.36 mm, 1.18 mm, and 0.6 mm.
- Shape: The shape of fine aggregate can also have an impact on the properties of the concrete. The most common shapes of fine aggregate are rounded and angular. Rounded aggregates are smooth and provide good workability, while angular aggregates are more jagged and provide better bonding between the aggregate and the cement paste.
- Texture: The texture of fine aggregate is related to the surface characteristics of the particles. The most common types of fine aggregate textures are smooth, rough, and porous. Smooth textures provide good workability, while rough and porous textures provide better bonding between the aggregate and the cement paste.
- Strength: The strength of fine aggregate is typically measured in terms of its compressive strength, which is the amount of pressure the aggregate can withstand before it fails. The compressive strength of fine aggregate can range from 5 MPa to 60 MPa, depending on the type of sand or crushed stone used.
In addition to the above characteristics, there are other factors that can affect the properties of fine aggregate, such as its fineness modulus, grading, and silt content. It’s important to choose the right type of fine aggregate for a particular concrete mixture, based on the desired properties of the finished product. Fine aggregates are also used in asphalt mixtures, plastering and in various construction works.
