A crystalline admixture is a concrete admixture, produced in liquid or powder form, that is added to the concrete of buildings under construction. It forms regular crystalline fibres within the capillary pores of the concrete and keeps it permanently watertight — in BS 8102 terms, a Type B (structurally integral) approach. Many brands manufacture it in liquid or powder form with some variation in composition, but every product serves the same purpose.
Where Are Crystalline Admixtures Used?
They are used in every concrete application where crystalline capillary watertightness is required:
- Foundations and reinforced concrete retaining walls
- Tunnels and dams
- Bored pile foundations
- Precast concrete elements
- Potable water and wastewater tanks
- Water treatment plants
- Swimming pools
- Lift pits
- Underground car parks
- Any area permanently exposed to water
Advantages of Crystalline Admixtures
- Protects the concrete against both positive and negative water pressure.
- Thanks to the natural mineral fibres it contains, it prevents the sudden cracking that shrinkage can cause in concrete.
- It remains permanently active during curing and on every subsequent contact with water, filling the capillary pores of the concrete with insoluble nano-scale crystals for lasting watertightness.
- It is generally a non-toxic admixture, manufactured to health-compliant standards.
- It has a positive effect on cost in terms of labour and time.
- No additional waterproofing system is needed.
- Activated whenever water or similar liquids arrive, it keeps producing nano-crystals in the capillary pores throughout the concrete's service life, sealing all capillaries, micro-cracks and voids of up to 1-2 mm.
- It improves efficiency, cuts costs and increases durability. By extending the life of the concrete, it reduces overall expenditure.
Points to Watch
When designing the concrete mix, the aggregate, chemical admixtures and cement type must be taken into account and the necessary tests carried out. Care must be taken during batching, pouring and placing, and the concrete must be poured to the relevant standards. The mix design and placement techniques must be chosen so that no voids or segregation occur in the concrete.
When the application is carried out to standard, the results are excellent. To use a crystalline admixture in your project, fill in the building information form.