Calcium free concrete invented
After eight years of research for perfecting the concrete without Portland cement, the product is now ready for its commercial sale. The new mix was used at the airport which the Wagners built near Toowoomba, Brisbane West Wellcamp.
Trials on pre-cast tunnel segments of the Wagners' earth friendly concrete (EFC), as they call it, have been completed in Malaysia and, last week, at Doha in Qatar. The concrete uses fly ash and slag, recycled from steel making and coal-fired power stations, is combined with chemical activators to create a geopolymer binder.
EFC does not need added protection from corrosion, and its flexural strength and low shrinkage makes it perfect for underground tunnels.