Description

The construction sector generates about a third of all waste in Europe. The use of concrete compliant with Minimum Environmental Criteria (CAM) turns waste into a resource, triggering the circular economy on site.

01From demolition to aggregate

Recycled aggregates are obtained by treating inert waste from Construction and Demolition (C&D). The industrial process involves crushing, de-ironing and screening. The resulting material, classified as End of Waste, partially replaces naturally quarried gravel and crushed stone.

02NTC requirements and structural limits

The use of recycled aggregates alters the mix's rheological performance. The presence of old mortar adhering to the stone grains increases porosity, water absorption and hygrometric shrinkage. For this reason, NTC 2018 limits substitution for structural concrete to maximum percentages ranging from 20% to 30% for ordinary classes, requiring carefully balanced mix designs.

Technical identity

Standards

European and international references applicable.

CAM EdiliziaNTC 2018UNI 11104UNI 8520-2

Physical properties

Elastic modulus (E)~28 GPa (marginal reduction)
Hygrometric shrinkageMaggiore (richiede additivi)
Water absorptionFino al 10% (bilanciabile)
Strength (fck)Parificabile a mix vergine

Usage environment

In Italy, the Decree of 23 June 2022 makes a minimum content of recovered/recycled material (at least 5% by total weight) mandatory for all concretes used in public works.

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