The term aggregate can be defined as a piece of mineral or recycled rock, measuring up to 125 mm, which is mainly used in the field of construction for building works (concrete, buildings, bridges) and civil engineering (roads, highways, railways).

These aggregates come from quarrying and sand pits (loose rock, solid rock) but also through marine extraction by dredging. As environmental standards become increasingly stringent, the development of aggregate recycling, resulting from mobile sites or the recovery of industrial products such as clinker, is growing and will certainly gain prominence over the coming years.

There are two families of aggregates:
  • “Rolled” aggregates as they are naturally shaped by lapping over time, usually by the tides
  • “Crushed” aggregates as their shape is angular, resulting from mechanical processing such as crushing (fragmentation)
To be used, aggregates are classified according to their particle sizes. To do this, they undergo several treatments such as crushing and, above all, screening to calibrate and sort products by recoverable dimensional class, characterised by the lowest dimension (mm) or “d” and largest dimension or “D”:
Name (France) d D
Fines 0 0.63
Sand 0 6.3
Loose gravel 2 ≤ 31.5
Bank gravel 0 ≤ 100
Stones 20 ≤ 150

For nearly a century, the GIRON company and its teams have worked with customers on material screening operations. Our technicians advise and offer a full range of metal and synthetic screening products to enable our customers to obtain the fairest cost per screened tonne, while complying with the usual specifications and standards of their productions.