Concrete is one of the commonly used construction materials, but when used on its own, it can shrink or crack easily. This is one of the main reasons why most constructors prefer to use aggregates with concrete in various projects. Aggregates are crushed or blasted materials from natural stones, and they come in different sizes and shapes that you must select carefully for your projects. The size and shape you choose will determine how easy it will be to use the concrete. The following are the common classifications of aggregates in Essex with regards to the size.
After aggregate is crushed, it is usually sieved, and the process is used to differentiate the coarse aggregate from fine ones. If a 4.75 mm sieve is used and some of the aggregates remain on it after sieving, then those are called coarse aggregates. They are larger in size and are mostly used in structures that need more strength. The coarse aggregates come in different diameters ranging from 9.5 mm to 37.5 mm. Their size reduces the quantity of water and concrete needed in the mixture, and the common types include gravel, boulders and cobble.
Most constructors use 20 mm aggregates in regular constructions that require more strength and 40 mm aggregates in constructions that require normal strength. Medium coarse gravel comes in diameters ranging between 8 mm and 16 mm while boulders have a diameter of more than 250 mm. Any company dealing with aggregates in Essex can help you choose the right coarse aggregates for your structure with the help of your constructor.
Fine aggregates are the ones that pass through a 4.75 mm sieve during the process. Natural sand usually falls under this category, but there are other materials like silt and clay that are classified as fine aggregates. In most cases, these aggregates are used together with coarse aggregates to ensure there are no
spaces between them. Anything smaller than 9.5 mm is also categorized under fine aggregates, and TJC Transport can help you select the best one for your application.
The aggregates also come in different shapes regardless of their size.
- Angular: these are mostly found from crushed rocks, and they have rough surfaces with properly defined edges. They usually have stronger cohesion which makes them perfect for structures that require high strength.
- Elongated: these have lengths that are more than other dimensions. Aggregates are classified as elongated when their length is more than 180% of their other dimensions.
- Flaky: these have longer lengths and widths than thickness.
- Rounded: these have round shapes that are like gravels found on seashores. They are easier to use because of their roundness, and they don’t require a lot of water or cement during construction. However, their shapes reduce cohesion which gives them a weaker bond.
- Irregular: these are harder to work with because of multiple shapes they come in, but they are more cohesive than rounded aggregates.