Air Entrainer (Air-Entraining Agent Powder) is a specialized powdered admixture designed to intentionally introduce and stabilize a controlled amount of microscopic air bubbles (typically 4–7% air content) into fresh concrete or mortar mixtures. It appears as a white to off-white, free-flowing fine powder that disperses easily during mixing.
This additive significantly enhances the durability of concrete, particularly in freeze-thaw environments, by creating tiny, evenly distributed air voids that act as internal pressure relief chambers when water freezes and expands.
Key Features & Advantages
- Excellent Freeze-Thaw Resistance — Dramatically improves concrete durability in cold climates by reducing spalling and scaling from ice expansion.
- Improved Workability & Cohesion — Makes fresh concrete more plastic, cohesive, and easier to place/finish with less bleeding and segregation.
- Increased Resistance to De-icing Salts — Better withstands chemical attack from road salts in winter conditions.
- Enhanced Pumpability & Flow — Air bubbles act as ball bearings, improving flow for pumped or self-compacting concrete.
- Reduced Permeability — Air voids help interrupt capillary pores, lowering water absorption.
- Low Dosage & Cost-Effective — Effective at 0.005–0.05% by cement weight, offering great performance value.
- Good Compatibility — Works with most cements, superplasticizers (PCE), and other admixtures.
Typical Applications
- Exterior concrete exposed to freezing and thawing cycles (roads, sidewalks, bridges, parking lots)
- Precast concrete elements in cold regions
- Masonry mortars and renders for improved workability and durability
- Lightweight concrete and insulating concrete
- Mass concrete pours requiring reduced cracking risk
