Geopolymers-based application for the up-cycling utilization of construction and demolition waste from the 2016 central Italy earthquakes

The 2016 seismic sequence in central Italy produced huge amounts of rubble. The need to recycle construction and demolition waste (CDW) to facilitate reconstruction process is therefore a problem of highest concern for quantities involved. In addition, CDW from rubble is very difficult to recycle being an extremely heterogeneous material. In this study, in order to produce mortars, the complete replacement of natural aggregate was investigated using the finest as-received CDW (0–8 mm) produced by local plants that managed the 2016 earthquake rubble. Results revealed that samples containing 60 wt.% CDW, metakaolin as precursor and K-silicate as alkaline reagent, have mechanical properties up to 28.7 MPa and mostly in the range of structural ordinary cementitious materials, suggesting that even the CDW fine fractions could be used in the production of upcycling mortars