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Last edited 25 Sep 2020
Gravel v hardcore v aggregates
Gravel is a loose aggregation of small, variously sized fragments of rock which can either be naturally-formed or manufactured. Gravel can be used for the manufacture of concrete, as well as for mixing with asphalt as part of road construction. It can be used as the base layer for roads before being covered with tarmac, and is also commonly used to surface roadways.
The term 'hardcore' refers to the mass of solid materials used as a make-up, formation material to raise levels, fill irregularities in excavations and create a firm and level working base onto which heavy load-bearing surfaces such as stone or concrete can be laid. Hardcore helps evenly spread imposed loads. Hardcore may be used in the formation of roads, paving, driveways, foundations, ground floor slabs, and so on. It may also be used on its own to form a temporary road surface on construction sites. Gravel can be used to make up a hardcore level.
Aggregate is a material used in construction as a means of stabilising and reinforcement, included, for example as a component of concrete and cement. It is a broad category which includes coarse-to-medium grained particulate materials such as sand, gravel, crushed stone, slag, and so on. Aggregates are also used in construction to provide drainage, fill voids, protect pipes, and to provide hard surfaces.
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