Rapid Hardening Cement (RHC) develops high early compressive strength due to higher C₃S content and finer grinding. Because of this early strength gain, it is widely used in situations where speed of construction and early load application are required. The major uses of rapid hardening cement are explained below.
Uses of Rapid Hardening Cement
1. Road, Pavement, and Highway Construction
Rapid hardening cement is extensively used in road construction where early opening to traffic is necessary. Due to high early strength, concrete pavements achieve required load-bearing capacity within a short time. This reduces traffic disruption and construction downtime compared to ordinary Portland cement (OPC).
It is particularly useful in:
- Urban road rehabilitation
- Airport runway repairs
- Industrial yard pavements
2. Cold Weather Concreting
In cold regions, hydration reaction slows down and early strength development becomes critical. Rapid hardening cement generates higher heat of hydration due to increased C₃S content, which accelerates strength gain and reduces the risk of frost damage during early stages of concrete setting.
This makes RHC suitable for winter concreting where temperature control is a concern.
3. Early Removal of Formwork
Because RHC gains sufficient strength in a shorter period, formwork can be removed earlier compared to conventional cement concrete. This increases construction speed and allows reuse of formwork in fast-track projects.
It is particularly advantageous in:
- Multistorey building construction
- Bridge deck casting
- Precast yard operations
4. Precast Concrete Structures
Rapid hardening cement is widely used in precast concrete production such as:
- Precast slabs
- Electric poles
- Pillars and beams
- Concrete blocks and pipes
High early strength allows faster demoulding and increases production efficiency in precast industries.
5. Repair and Maintenance Works
RHC is commonly used for repair works where early strength gain is required. Examples include:
- Building structural repairs
- Patch repair of pavements
- Industrial floor rehabilitation
Due to rapid setting and hardening characteristics, repaired sections can be put into service quickly.
Important Note on Sulfate Exposure
Rapid hardening cement is not specifically designed for sulfate resistance. In environments exposed to severe sulfate attack, sulfate resisting cement should be used instead. Selection of cement type must follow durability requirements specified in relevant building codes.