Editing Concrete (section)

===Ancient times===
Concrete floors were found in the royal palace of [[Tiryns]], Greece, which dates roughly to 1400 to 1200 BC.<ref>{{cite book|author1=Heinrich Schliemann|author2=Wilhelm Dörpfeld|author3=Felix Adler|title=Tiryns: The Prehistoric Palace of the Kings of Tiryns, the Results of the Latest Excavations|url=https://archive.org/details/bub_gb_pw4BAAAAMAAJ|year=1885|publisher=Charles Scribner's Sons|location=New York|pages=[https://archive.org/details/bub_gb_pw4BAAAAMAAJ/page/n266 190], 203–204, 215}}</ref><ref>{{cite arXiv|first =Amelia Carolina|last = Sparavigna|title = Ancient concrete works|eprint= 1110.5230|class = physics.pop-ph|year = 2011}}</ref> Lime mortars were used in Greece, such as in Crete and Cyprus, in 800 BC. The [[Assyria]]n Jerwan Aqueduct (688 BC) made use of [[waterproof concrete]].<ref>Jacobsen T and Lloyd S, (1935) "Sennacherib's Aqueduct at Jerwan," ''Oriental Institute Publications'' 24, Chicago University Press</ref> Concrete was used for construction in many ancient structures.<ref>{{Cite journal|title=Ancient Concrete Structures|author=Stella L. Marusin|journal=Concrete International|volume=18|issue=1|pages=56–58|date=1 January 1996|url= https://www.concrete.org/publications/internationalconcreteabstractsportal/m/details/id/9377}}</ref>

Mayan concrete at the ruins of [[Uxmal]] (AD 850–925) is referenced in ''Incidents of Travel in the Yucatán'' by [[John Lloyd Stephens|John L. Stephens]]. "The roof is flat and had been covered with cement". "The floors were cement, in some places hard, but, by long exposure, broken, and now crumbling under the feet." "But throughout the wall was solid, and consisting of large stones imbedded in mortar, almost as hard as rock."

Small-scale production of concrete-like materials was pioneered by the [[Nabataea|Nabatean]] traders who occupied and controlled a series of oases and developed a small empire in the regions of southern Syria and northern Jordan from the 4th century BC. They discovered the advantages of [[hydraulic lime]], with some self-cementing properties, by 700 BC. They built [[kiln]]s to supply mortar for the construction of [[rubble masonry]] houses, concrete floors, and underground waterproof [[cistern]]s. They kept the cisterns secret as these enabled the Nabataeans to thrive in the desert.<ref name="Gromicko-2016">{{Cite web|url=https://www.nachi.org/history-of-concrete.htm |title=The History of Concrete |last1=Gromicko|first1=Nick|last2=Shepard|first2=Kenton|date=2016|website=International Association of Certified Home Inspectors, Inc.|access-date=27 December 2018}}</ref> Some of these structures survive to this day.<ref name="Gromicko-2016" />

In the [[Ancient Egypt]]ian and later [[Roman Empire|Roman]] eras, builders discovered that adding [[Pozzolan|volcanic ash]] to [[Lime (material)|lime]] allowed the mix to set underwater. They discovered the [[Pozzolanic activity#Reaction|pozzolanic reaction]].<ref>{{Cite web |date=2023-01-06 |title=Riddle solved: Why was Roman concrete so durable? |url=https://news.mit.edu/2023/roman-concrete-durability-lime-casts-0106 |access-date=2024-10-25 |website=MIT News {{!}} Massachusetts Institute of Technology |language=en}}</ref>