| abstract |
A low cement content concrete composition for mixing with water and for foundation applications, the composition comprising cement, aggregate, a plasticiser effective to achieve a flow of at least 500 mm when the concrete composition is mixed with water and an air-entrainer. The plasticiser may be a lignosulphonate. Preferably the aggregate : cement ratio by weight is from 5:1 to 12:1, most preferably from 7:1 to 9:1. The water : cement ratio is from 0.6:1 to 1:1, most preferably from 0.75:1 to 0.85:1. A process for delivering a concrete composition to a site is also disclosed, the process comprising: <SL> <LI>(i) providing a first mixture comprising cement, aggregate and water; <LI>(ii) providing a second mixture comprising one or more admixtures; <LI>(iii) adding the second mixture to the first mixture; <LI>(iv) conveying the first and second mixtures to a site, wherein there is no mixing of the first and second mixtures during transit; and <LI>(v) mixing the first and second mixtures together at site prior to application. </SL> |