By replacing some of the cement mix in concrete with a particular type of clay, the steel reinforcement can also be replaced by aluminium, according to European researchers.
Known as Everlasting Concrete, they say it produces 80% less CO₂ that current products and requires no maintenance. Consequently, the researchers were recently awarded SINTEF’s Prize for Research Excellence.
The SINTEF researchers have also shown that traditional steel reinforcement can be replaced by aluminium in situations where the burnt blue clay is used to replace at least half of the cement content of the concrete. They say that burnt blue clay is a material plentifully available as a natural resource.
The clay confers a level of acidity on the concrete that the aluminium can tolerate. This signals an end to corrosion issues, according to the researchers, that make preventative maintenance essential for as long as concrete has been using reinforced steel.
Everlasting Concrete has already been used in a road bridge across the Grodola River in Sunndal in Norway and the entrance to the Geitbatmuseet boat heritage museum in Trondelag. The next project will be a concrete stairway at the Norwegian University of Science and Technology.
SINTEF is one of Europe’s largest independent research institutes, focusing on innovation, development and research for business and the public sector since 1950.