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Lightweight aggregates

In the UK the most commonly used lightweight aggregate is LYTAG, a sintered fly ash, also known as pulverised fuel ash (pfa). Other aggregates, made from a variety of raw materials, are shown in the Table below.

Aggregate type Trade name Dry density kg/m3
Furnace clinker   720-1040
Processed fly ash/pfa Lytag 770-960
Foamed blastfurnace slag   670-920
Expanded clay, shale and slate Aglite, Leca, Solite 320-960
Pumice   480-880
Pelletized expanded slag Pellite 800-1000
Wood and plastic particles   320-480
Expanded vermiculite   60-160

The density of the resulting concrete will depend on the type of aggregate used. Lightweight aggregates may be used for the coarse aggregate in conjunction with natural fines, or lightweight can be used for both coarse and fine aggregates.


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Abrasion resistance of floors containing lightweight coarse aggregate