Ancient Roman builders used cocciopesto (ceramic fragments) in addition to volcanic ash as a source of reactive aluminosilicates for their mortar and concrete formulations.
In this paper we looked into the chemistry of mortars from ancient water infrastructure serving Rome and Pompeii.
We found a C-A-S-H (calcium-aluminum-silicate-hydrate) binding phase at the ceramic-cement interfaces, which plays a critical role in the strengthening of these ancient construction materials.
These results could inspire the development of more durable modern concrete formulations.