ISF Ultra High Performance Concrete
Ultra High Performance Concrete (UHPC) is characterized by a very high compressive strength (above 150 MPa) and extreme durability, even when exposed to high aggressive environmental impacts. All these characteristics make it an alternative to other construction materials (e.g. steel) for the construction of transport and hydraulic facilities, high-rise buildings, as well as for special mine structures, structures for military application and high aesthetic architectural elements and details. At the same time, UHPC is a material, which complies with the policy of sustainable development by reducing the need for maintenance and rehabilitation of the facilities. Iron-silicate fines (ISF) are one of the best materials for making UHPC, which bring plenty of benefits in the structures and elements:
» Compact the macro- and microstructure due to the small grain size;
» Increase the density by additional interaction with other ingredients;
» Increase the workability of the fresh mixtures;
» Reduce natural raw material utilization;
» Create long-term life products;
» Make sustainable final products.
Standard ISF UHPC mix design includes:
1. ISF = 1150kg/m3;
2. Cement = 820kg/m3;
3. Fly ash = 380kg/m3;
4. Water/Cement =0,3
The density of ISF UHPC is about 2,4 kg/m3 and the compressive strength exceeds 100MPa. In case thermal treatment is applied, the mechanical properties of concrete could increase by 30%. For application in thin structural elements subjected to flexture, it is recommended to use short (6 to 8 mm) steel fibres – 2% by volume.