British Land used Keltbray’s Earth Friendly Concrete, which relies on blast furnace slag and fly ash, for a project in London. Engineers estimate that converting the piling mix helped reduce embodied carbon by 240 metric tons, or 45%.
Keltbray used Earth Friendly Concrete for the piled foundations of the development.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.
Stuart Norman, Keltbray’s managing director for piling, said: “EFC is particularly suited for permanent works use within piled foundations and this is a brilliant milestone to have reached at Canada Water and for construction in the UK in general. We are very confident in the performance and durability of EFC and are working constructively with all stakeholders to develop the full suite of engineering properties.”
British Land’s head of development for Canada Water, Philip Tait, said: “As part of our new sustainability strategy launched last year, we’ve committed to achieving a net zero carbon portfolio by 2030 with a focus on reducing embodied carbon in our developments, and this is an important initiative in helping us reach this target. Keltbray and its partners have been brilliant to work with and we look forward to exploring further opportunities with EFC across our Canada Water development.”