CLEVA CRETE Admixtures are classified as Permeability-Reducing Admixtures (PRAs) because they are specifically engineered to enhance the durability and water resistance of concrete by reducing its permeability. Here’s how they achieve this:
- Chemical Reaction for Densification
CLEVA CRETE Admixtures contain active components that activate with the water and calcium hydroxide produced during cement hydration. This reaction forms insoluble compounds, such as calcium silicate hydrate (C-S-H), which prevents the establishment of micro voids and capillaries in the concrete matrix, leading to:
- A denser structure.
- Inhibited capillary porosity.
- Blocking Water Pathways
By preventing the capillary pores, CLEVA CRETE Admixtures block pathways that water or vapour would otherwise use to infiltrate the concrete. This minimises:
- Penetration of water under pressure.
- The vapour intrusion of hazardous substances like chlorides, sulphates, carbonation agents and other volatile organic compounds (VOCs) into indoor environment.
- Self-Sealing Properties
CLEVA CRETE admixtures can provide self-healing characteristics, where microcracks formed during concrete curing or use can be filled by activated reactions. These reactions occur when moisture activates the remaining unhydrated particles, enhancing the long-term durability.
- Durability Under Hydrostatic Pressure
CLEVA CRETE’s Permeability-Reducing Water-Pressure (PRWP) products, such as 842 WP, are specifically designed for use in structures exposed to constant water pressure or hydrostatic pressure, such as:
- Basements
- Underground tanks
- Coastal or water-bound structures
This ensures the concrete maintains its integrity even in challenging conditions.
- Lifecycle Benefits
By reducing permeability, CLEVA CRETE Admixtures contribute to:
- Extended service life of the concrete structure by preventing moisture-induced deterioration.
- Improved resistance to freeze-thaw cycles and sulphate attack.
- Enhanced protection of embedded steel reinforcement from corrosion.
CLEVA CRETE Admixtures help create concrete that is more durable, long-lasting, and less susceptible to water-related damage, aligning with industry standards for permeability-reducing performance.