Roman noblewoman’s tomb reveals secrets of ancient concrete resilience

Over time, concrete cracks and crumbles. Well, most concrete cracks and crumbles. Structures built in ancient Rome are still standing, exhibiting remarkable durability despite conditions that would devastate modern concrete. One of these structures is the large cylindrical tomb of first-century noblewoman Caecilia Metella. New research shows that the quality of the concrete of her tomb may exceed that of her male contemporaries' monuments because of the volcanic aggregate the builders chose and the unusual chemical interactions with rain and groundwater with that aggregate over two millennia.

source https://www.sciencedaily.com/releases/2021/10/211008134107.htm