Most research on recycled aggregates concrete concern aggregates produced from concrete waste, rather
than actual construction and demolition waste. Different investigations have assessed that sulfonatedbased
superplastizers are not as efficient in recycled aggregates concrete than on natural aggregates concrete,
but no significant loss of polycarboxylic-based superplasticizer efficiency has been reported. This
may not be valid when the aggregates are sourced from actual construction and demolition waste, due
to the higher porosity, roughness, and weaker mechanical properties of aggregates produced from this
source. This paper analyses the mechanical properties of superplasticized concrete with the incorporation
of construction and demolition waste. Recycled aggregates produced from construction and demolition
waste were taken directly from plants and used as aggregates without screening or treatment, emulating
what would happen in a practical application by the concrete industry. The results of the tests and the
superplasticizer’s efficiency are compared with results on natural aggregate concrete compositions and
on analogue recycled concrete aggregate concrete compositions with and without superplasticizers.
The composition of the different construction and demolition waste aggregates is considered during
the analysis of results. Evidence was found that when recycled aggregates are sourced from construction
and demolition waste, polycarboxylic-based superplasticizers perform satisfactorily but may not be as
efficient as in natural aggregate concrete compositions.