The usage of cement varies based on the location of the structure and design criteria.
Mostly OPC cement has been used to construct a general structure, but it is not suitable for underground construction because OPC cement does not have sulphate resistant capacity.
So we have different types of cement for every usage condition.
What is Rapid Hardening Cement?
RHC is a special cement where high early strength is required. Another name for Rapid hardening cement is “High early strength cement”. It attains compressive strength in a short period.
- It has a higher ratio of lime and balanced constituents of the OPC cement.
- A higher percentage of C3S (Tricalcium silicate) has been added into the cement to attain the higher strength in a short period.
- Rapid hardening cement produces the strength at the age of 3 days is equal to the 7 days strength of OPC cement with the same water-cement ratio.
- Lighter than OPC cement.
- The minimum curing period is enough.
- We can remove the formwork earlier because it produces a higher strength in a short period. So we can re-use the shuttering material for other work.
- It is used where higher strength is required in a short period for further construction activity.
- It will reduce the workability compared to ordinary portland cement because it is quick hydration process.
- High cost compared to other types of cement.
Another rapid hardening cement exists in construction named “Extra Rapid Hardening Cement”.
Extra Rapid Hardening Cement
Extra Rapid Hardening Cement has been manufactured by adding 3% of calcium chloride with Rapid Hardening Portland Cement.
It gives 25% higher strength than RHP Cement in 2 days and 10 to 20% higher at 7 Days. Extra rapid hardening cement is preferable to use when very high strength is required in a short period.
Generally, these types of cement are used in waterlogged areas, bridges, dams, etc., Because those structures required high strength required in a short period to continue the flow of construction activity.