Construction aggregates

Construction aggregates Mineral Planning Factsheet Expert | Impartial | Innovative Aggregates are the most commonly used construction minerals in the UK. They are widely distributed with a range of potential sources and, while a low cost product, are used in very large quantities. They are essential for constructing and maintaining what is literally the physical framework of the buildings and infrastructure on which our society depends. Aggregates are normally defined as being hard, granular 1 materials which are suitable for use either on their own or with the addition of cement, lime or a bituminous binder in construction. Important applications include concrete, mortar, roadstone, asphalt, railway ballast, drainage courses and bulk fill. European Standard (BS EN12620) defines aggregates as ‘granular material used in construction. Aggregates may be natural, manufactured or recycled.’ These are further defined as: Natural aggregates — aggregates from mineral sources which have been subject to nothing more than physical processing (crushing and sizing). Manufactured aggregates — aggregates of mineral origin resulting from an industrial process involving thermal or other modification e.g. slag. Recycled aggregates — aggregates resulting from the processing of inorganic materials previously used in construction e.g. construction and demolition waste. In Britain, however, it is common practice to distinguish between primary aggregates and alternative sources, such as secondary aggregates and recycled aggregates. Primary aggregates are produced from naturally occurring mineral deposits, extracted specifically for use as aggregates and used for the first time. Most construction aggregates are produced from hard, strong rock formations by crushing to produce crushed rock aggregates or from naturally occurring particulate deposits such as sand and gravel. The most important sources of crushed rock in Britain are limestone (including dolomite), igneous rock and sandstone. Sand and gravel can be either land-won or marine dredged. Primary aggregates fall within the European definition of natural aggregates. The term aggregate mineral is also used for any naturally occurring material that is suitable for aggregates use. Some rock types, notably limestone/dolomite, are suitable for both aggregates and non-aggregates applications. Secondary aggregates are usually defined as (a) aggregates obtained as a by-product of other quarrying and mining operations, such as china clay waste, slate waste and colliery spoil (minestone), or (b) aggregates obtained as a by-product of other industrial processes, such as blast furnace/steel slag, coal-fired power station ash, incinerator ash, and spent foundry sand. In European specifications, mineral waste sold as aggregates is classified as natural aggregates, and by-product aggregates derived from industrial processes are classed as manufactured aggregates. Recycled aggregates are an important source of aggregates in Britain. They arise from various sources including demolition or construction of buildings and structures, or 1 Aggregates This factsheet provides an overview of aggregates supply in the UK. It forms part of a series on economically important minerals that are extracted in Britain and is primarily intended to inform the land-use planning process. It is not a statement of planning policy or guidance; nor does it imply Government approval of any existing or potential planning application in the UK administration. June 2019 Gravel aggregate. 1 However, a proportion of aggregates sales are for constructional fill or other uses where soft and non- granular material may be acceptable or even specified.

Construction aggregates

Documents

asphalt aggregate

material

asphalt concrete

mortar

roadstone

asphalt

railway ballast

drainage courses