The life cycle assessment of recycled concrete usually adopts a system boundary from cradle to gate, covering raw material production, transportation, and concrete preparation.
The mix design determines the amount of cement, natural aggregates, recycled aggregates, and water used, as well as transportation demand and preparation energy consumption.
If we only compare whether to use recycled aggregates at the end, it is easy to overlook the environmental rebound caused by cement increment.
Moving the life cycle assessment to the mix design stage can achieve synergistic optimization of carbon footprint and mechanical properties, making it a suitable multi-objective design case for green building materials courses in universities.
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