Australian firm develops cement-free concrete
Alternative concrete mix saves carbon at London’s Canada Water.
UK firm Keltbray reckons that using cement-free concrete has saved developer British Land 240 tonnes of carbon on its Canada Water site in southeast London.
Earth Friendly Concrete (EFC) is a concrete manufactured by Australian firm Wagners using blast furnace slag and fly ash instead of ordinary Portland cement. It is supplied in the UK by Capital Concrete.
Consulting engineer AKT II supported the project and pursued low carbon products for use on this scheme.
By converting the piling mix from a traditional CEM IIIA mix to an EFC mix, a saving is made of approximately 45% of the embodied carbon, it has been calculated. The piles themselves are designed as 600mm in diameter to depths of up to 25 metres, installed using a continuous flight auger.
Keltbray has also secured the contract at Canada Water to install the pile caps and the basement slab. Testing is continuing for a stronger C40/50 EFC mix, which, if adopted, would further reduce the embodied carbon within the scheme.