high performance concrete

 high performance concrete

1. In high performance concrete mix design as water cement ratio adopted is low, super plasticizers are
necessary to maintain required workability. As the percentage of mineral admixtures is increased in
the mix, the percentage of super plasticizer should also be increased, for thorough mixing and for
obtaining the desired strength.

2. In M80 and M90 grades of concrete as the water-cement ratios of 0.23 and 0.21 are insufficient to
provide the workability, (the easiness of handling of concrete in all the stages) hence super plasticizer
are necessary for M80 and M90 grades of concrete.

3. In case of combination percentage replacement of mineral admixtures the maximum compressive
strength achieved in M90 grade concrete is 92.4 Mpa with replacement of 33% flyash and 15.13%
Metakaolin

4. In case of combination percentage replacement of mineral admixtures the maximum compressive
strength achieved in M80 grade concrete is 82.2 Mpa with replacement of 20% flyash and 13.23%
of metakaolin.

5. Mineral admixtures such as Flyash, micro silica, metakaolin, also contributes effectively for
achieving high strength.

6. As soon as crack pattern appears, sudden failure is observed in high strength concrete cubes.

7. The scope for using high strength concrete in our constructional activities are more such as precast,
prestressed bridges, multi-storied buildings, bridges and structures on coastal areas. To affect this
change, we will have to revive the designing of structures by encouraging use of high strength
concrete mixes associated with high performance also