Exposed aggregate precast cladding panel prodn. - has concrete poured on aggregate set in 3 mm fine sand which is brushed out after striking

摘要

The process is used in the precasting of cladding panels with a facing of naturally-occurring stone aggregates in relief, utilising a temporary fine sand layer to ensure that the stones stand proud of a special bedding mortar. Initially the stones are placed in a tray type mould on a vibrating table, the sand then being placed between stones to a depth of some 3mm. An appropriately coloured mortar of the same fine sand may next be placed, being followed by the backing layer of e.g. reinforced concrete. Once the unit has set and the mould has been struck the sand may be brushed from between the stones, or may simply be left on the table if the mould is bottomless.