Quake-proof cement mixed '1 300 years ago'
London - The Sixth Century builders of Hagia Sophia, the Byzantine cathedral still standing in Istanbul, discovered cement with earthquake-resistant properties 1 300 years before anyone else, a research team revealed on Wednesday.
Hagia Sophia, built as a church and subsequently turned into a mosque, still stands only because its creators discovered the cement.
Many of the surrounding buildings have long since succumbed to the ravages of time, including earthquakes, according to a report in the New Scientist.
The structure has withstood quakes of up to 7,5 on the Richter scale, according to the team, headed by Antonia Moropoulou from Athens' National Technical University.
The team found that the cement contained a calcium silicate matrix similar to that found in Portland cement, although the architects, Anthemius of Tralles and Isidore of Miletus, came up with their mix in 532.
Team member Ahmet Cakmak of Princeton University said volcanic ash or other silica was deliberately added to the mixture, producing a material that could absorb seismic activity.
"The Byzantians knew exactly what they were doing. They were very advanced scientists," he said.
The group hopes the mortar can be recreated to allow faithful restoration. - Sapa-DPA