Cement is to concrete what flour is to cake. Normally, cement makes up about 15% of concrete (in volume), with stone, water, sand and chemical admixtures making up the rest.
However, manufacturing cement has a high CO2 footprint – traditionally between 800 and 900 kg for every 1 000 kg and the global cement industry is responsible for 5% of total carbon emissions worldwide.
To address this, the cement industry and researchers have been working to reduce cement’s carbon footprint. Concrete now uses much less pure cement, compared with ten . . . twenty years ago.
Read more about efforts to reduce CO2 and find innovative alternatives to cement in concrete at: http://www.engineeringnews.co.za/article/concrete-market-sees-steady-reduction-in-cement-use-as-researchers-tackle-carbon-conundrum-2014-03-28/rep_id:3182
